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Publisher: Elsevier   (Total: 3157 journals)

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Showing 1 - 200 of 3160 Journals sorted alphabetically
A Practical Logic of Cognitive Systems     Full-text available via subscription   (Followers: 9)
AASRI Procedia     Open Access   (Followers: 15)
Academic Pediatrics     Hybrid Journal   (Followers: 35, SJR: 1.655, CiteScore: 2)
Academic Radiology     Hybrid Journal   (Followers: 24, SJR: 1.015, CiteScore: 2)
Accident Analysis & Prevention     Partially Free   (Followers: 96, SJR: 1.462, CiteScore: 3)
Accounting Forum     Hybrid Journal   (Followers: 27, SJR: 0.932, CiteScore: 2)
Accounting, Organizations and Society     Hybrid Journal   (Followers: 37, SJR: 1.771, CiteScore: 3)
Achievements in the Life Sciences     Open Access   (Followers: 5)
Acta Anaesthesiologica Taiwanica     Open Access   (Followers: 7)
Acta Astronautica     Hybrid Journal   (Followers: 417, SJR: 0.758, CiteScore: 2)
Acta Automatica Sinica     Full-text available via subscription   (Followers: 2)
Acta Biomaterialia     Hybrid Journal   (Followers: 27, SJR: 1.967, CiteScore: 7)
Acta Colombiana de Cuidado Intensivo     Full-text available via subscription   (Followers: 2)
Acta de Investigación Psicológica     Open Access   (Followers: 3)
Acta Ecologica Sinica     Open Access   (Followers: 10, SJR: 0.18, CiteScore: 1)
Acta Haematologica Polonica     Free   (Followers: 1, SJR: 0.128, CiteScore: 0)
Acta Histochemica     Hybrid Journal   (Followers: 3, SJR: 0.661, CiteScore: 2)
Acta Materialia     Hybrid Journal   (Followers: 262, SJR: 3.263, CiteScore: 6)
Acta Mathematica Scientia     Full-text available via subscription   (Followers: 5, SJR: 0.504, CiteScore: 1)
Acta Mechanica Solida Sinica     Full-text available via subscription   (Followers: 9, SJR: 0.542, CiteScore: 1)
Acta Oecologica     Hybrid Journal   (Followers: 12, SJR: 0.834, CiteScore: 2)
Acta Otorrinolaringologica (English Edition)     Full-text available via subscription  
Acta Otorrinolaringológica Española     Full-text available via subscription   (Followers: 3, SJR: 0.307, CiteScore: 0)
Acta Pharmaceutica Sinica B     Open Access   (Followers: 1, SJR: 1.793, CiteScore: 6)
Acta Poética     Open Access   (Followers: 4, SJR: 0.101, CiteScore: 0)
Acta Psychologica     Hybrid Journal   (Followers: 27, SJR: 1.331, CiteScore: 2)
Acta Sociológica     Open Access   (Followers: 1)
Acta Tropica     Hybrid Journal   (Followers: 6, SJR: 1.052, CiteScore: 2)
Acta Urológica Portuguesa     Open Access  
Actas Dermo-Sifiliograficas     Full-text available via subscription   (Followers: 3, SJR: 0.374, CiteScore: 1)
Actas Dermo-Sifiliográficas (English Edition)     Full-text available via subscription   (Followers: 2)
Actas Urológicas Españolas     Full-text available via subscription   (Followers: 3, SJR: 0.344, CiteScore: 1)
Actas Urológicas Españolas (English Edition)     Full-text available via subscription   (Followers: 1)
Actualites Pharmaceutiques     Full-text available via subscription   (Followers: 6, SJR: 0.19, CiteScore: 0)
Actualites Pharmaceutiques Hospitalieres     Full-text available via subscription   (Followers: 3)
Acupuncture and Related Therapies     Hybrid Journal   (Followers: 7)
Acute Pain     Full-text available via subscription   (Followers: 14, SJR: 2.671, CiteScore: 5)
Ad Hoc Networks     Hybrid Journal   (Followers: 11, SJR: 0.53, CiteScore: 4)
Addictive Behaviors     Hybrid Journal   (Followers: 17, SJR: 1.29, CiteScore: 3)
Addictive Behaviors Reports     Open Access   (Followers: 8, SJR: 0.755, CiteScore: 2)
Additive Manufacturing     Hybrid Journal   (Followers: 10, SJR: 2.611, CiteScore: 8)
Additives for Polymers     Full-text available via subscription   (Followers: 23)
Advanced Drug Delivery Reviews     Hybrid Journal   (Followers: 160, SJR: 4.09, CiteScore: 13)
Advanced Engineering Informatics     Hybrid Journal   (Followers: 11, SJR: 1.167, CiteScore: 4)
Advanced Powder Technology     Hybrid Journal   (Followers: 17, SJR: 0.694, CiteScore: 3)
Advances in Accounting     Hybrid Journal   (Followers: 8, SJR: 0.277, CiteScore: 1)
Advances in Agronomy     Full-text available via subscription   (Followers: 15, SJR: 2.384, CiteScore: 5)
Advances in Anesthesia     Full-text available via subscription   (Followers: 28, SJR: 0.126, CiteScore: 0)
Advances in Antiviral Drug Design     Full-text available via subscription   (Followers: 2)
Advances in Applied Mathematics     Full-text available via subscription   (Followers: 10, SJR: 0.992, CiteScore: 1)
Advances in Applied Mechanics     Full-text available via subscription   (Followers: 11, SJR: 1.551, CiteScore: 4)
Advances in Applied Microbiology     Full-text available via subscription   (Followers: 24, SJR: 2.089, CiteScore: 5)
Advances In Atomic, Molecular, and Optical Physics     Full-text available via subscription   (Followers: 14, SJR: 0.572, CiteScore: 2)
Advances in Biological Regulation     Hybrid Journal   (Followers: 4, SJR: 2.61, CiteScore: 7)
Advances in Botanical Research     Full-text available via subscription   (Followers: 2, SJR: 0.686, CiteScore: 2)
Advances in Cancer Research     Full-text available via subscription   (Followers: 33, SJR: 3.043, CiteScore: 6)
Advances in Carbohydrate Chemistry and Biochemistry     Full-text available via subscription   (Followers: 9, SJR: 1.453, CiteScore: 2)
Advances in Catalysis     Full-text available via subscription   (Followers: 5, SJR: 1.992, CiteScore: 5)
Advances in Cell Aging and Gerontology     Full-text available via subscription   (Followers: 4)
Advances in Cellular and Molecular Biology of Membranes and Organelles     Full-text available via subscription   (Followers: 12)
Advances in Chemical Engineering     Full-text available via subscription   (Followers: 27, SJR: 0.156, CiteScore: 1)
Advances in Child Development and Behavior     Full-text available via subscription   (Followers: 10, SJR: 0.713, CiteScore: 1)
Advances in Chronic Kidney Disease     Full-text available via subscription   (Followers: 9, SJR: 1.316, CiteScore: 2)
Advances in Clinical Chemistry     Full-text available via subscription   (Followers: 26, SJR: 1.562, CiteScore: 3)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 19, SJR: 1.977, CiteScore: 8)
Advances in Computers     Full-text available via subscription   (Followers: 14, SJR: 0.205, CiteScore: 1)
Advances in Dermatology     Full-text available via subscription   (Followers: 15)
Advances in Developmental Biology     Full-text available via subscription   (Followers: 12)
Advances in Digestive Medicine     Open Access   (Followers: 9)
Advances in DNA Sequence-Specific Agents     Full-text available via subscription   (Followers: 5)
Advances in Drug Research     Full-text available via subscription   (Followers: 25)
Advances in Ecological Research     Full-text available via subscription   (Followers: 44, SJR: 2.524, CiteScore: 4)
Advances in Engineering Software     Hybrid Journal   (Followers: 28, SJR: 1.159, CiteScore: 4)
Advances in Experimental Biology     Full-text available via subscription   (Followers: 8)
Advances in Experimental Social Psychology     Full-text available via subscription   (Followers: 46, SJR: 5.39, CiteScore: 8)
Advances in Exploration Geophysics     Full-text available via subscription   (Followers: 1)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 9)
Advances in Food and Nutrition Research     Full-text available via subscription   (Followers: 59, SJR: 0.591, CiteScore: 2)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 16)
Advances in Genetics     Full-text available via subscription   (Followers: 16, SJR: 1.354, CiteScore: 4)
Advances in Genome Biology     Full-text available via subscription   (Followers: 8, SJR: 12.74, CiteScore: 13)
Advances in Geophysics     Full-text available via subscription   (Followers: 6, SJR: 1.193, CiteScore: 3)
Advances in Heat Transfer     Full-text available via subscription   (Followers: 23, SJR: 0.368, CiteScore: 1)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 12, SJR: 0.749, CiteScore: 3)
Advances in Human Factors/Ergonomics     Full-text available via subscription   (Followers: 23)
Advances in Imaging and Electron Physics     Full-text available via subscription   (Followers: 2, SJR: 0.193, CiteScore: 0)
Advances in Immunology     Full-text available via subscription   (Followers: 36, SJR: 4.433, CiteScore: 6)
Advances in Inorganic Chemistry     Full-text available via subscription   (Followers: 8, SJR: 1.163, CiteScore: 2)
Advances in Insect Physiology     Full-text available via subscription   (Followers: 2, SJR: 1.938, CiteScore: 3)
Advances in Integrative Medicine     Hybrid Journal   (Followers: 6, SJR: 0.176, CiteScore: 0)
Advances in Intl. Accounting     Full-text available via subscription   (Followers: 3)
Advances in Life Course Research     Hybrid Journal   (Followers: 8, SJR: 0.682, CiteScore: 2)
Advances in Lipobiology     Full-text available via subscription   (Followers: 1)
Advances in Magnetic and Optical Resonance     Full-text available via subscription   (Followers: 8)
Advances in Marine Biology     Full-text available via subscription   (Followers: 18, SJR: 0.88, CiteScore: 2)
Advances in Mathematics     Full-text available via subscription   (Followers: 11, SJR: 3.027, CiteScore: 2)
Advances in Medical Sciences     Hybrid Journal   (Followers: 7, SJR: 0.694, CiteScore: 2)
Advances in Medicinal Chemistry     Full-text available via subscription   (Followers: 5)
Advances in Microbial Physiology     Full-text available via subscription   (Followers: 4, SJR: 1.158, CiteScore: 3)
Advances in Molecular and Cell Biology     Full-text available via subscription   (Followers: 23)
Advances in Molecular and Cellular Endocrinology     Full-text available via subscription   (Followers: 8)
Advances in Molecular Toxicology     Full-text available via subscription   (Followers: 7, SJR: 0.182, CiteScore: 0)
Advances in Nanoporous Materials     Full-text available via subscription   (Followers: 3)
Advances in Oncobiology     Full-text available via subscription   (Followers: 2)
Advances in Organ Biology     Full-text available via subscription   (Followers: 1)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 17, SJR: 1.875, CiteScore: 4)
Advances in Parallel Computing     Full-text available via subscription   (Followers: 7, SJR: 0.174, CiteScore: 0)
Advances in Parasitology     Full-text available via subscription   (Followers: 5, SJR: 1.579, CiteScore: 4)
Advances in Pediatrics     Full-text available via subscription   (Followers: 24, SJR: 0.461, CiteScore: 1)
Advances in Pharmaceutical Sciences     Full-text available via subscription   (Followers: 12)
Advances in Pharmacology     Full-text available via subscription   (Followers: 16, SJR: 1.536, CiteScore: 3)
Advances in Physical Organic Chemistry     Full-text available via subscription   (Followers: 8, SJR: 0.574, CiteScore: 1)
Advances in Phytomedicine     Full-text available via subscription  
Advances in Planar Lipid Bilayers and Liposomes     Full-text available via subscription   (Followers: 3, SJR: 0.109, CiteScore: 1)
Advances in Plant Biochemistry and Molecular Biology     Full-text available via subscription   (Followers: 10)
Advances in Plant Pathology     Full-text available via subscription   (Followers: 5)
Advances in Porous Media     Full-text available via subscription   (Followers: 5)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 19)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 20, SJR: 0.791, CiteScore: 2)
Advances in Psychology     Full-text available via subscription   (Followers: 64)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 6, SJR: 0.371, CiteScore: 1)
Advances in Radiation Oncology     Open Access   (SJR: 0.263, CiteScore: 1)
Advances in Small Animal Medicine and Surgery     Hybrid Journal   (Followers: 3, SJR: 0.101, CiteScore: 0)
Advances in Space Biology and Medicine     Full-text available via subscription   (Followers: 6)
Advances in Space Research     Full-text available via subscription   (Followers: 404, SJR: 0.569, CiteScore: 2)
Advances in Structural Biology     Full-text available via subscription   (Followers: 5)
Advances in Surgery     Full-text available via subscription   (Followers: 11, SJR: 0.555, CiteScore: 2)
Advances in the Study of Behavior     Full-text available via subscription   (Followers: 34, SJR: 2.208, CiteScore: 4)
Advances in Veterinary Medicine     Full-text available via subscription   (Followers: 18)
Advances in Veterinary Science and Comparative Medicine     Full-text available via subscription   (Followers: 14)
Advances in Virus Research     Full-text available via subscription   (Followers: 5, SJR: 2.262, CiteScore: 5)
Advances in Water Resources     Hybrid Journal   (Followers: 47, SJR: 1.551, CiteScore: 3)
Aeolian Research     Hybrid Journal   (Followers: 6, SJR: 1.117, CiteScore: 3)
Aerospace Science and Technology     Hybrid Journal   (Followers: 352, SJR: 0.796, CiteScore: 3)
AEU - Intl. J. of Electronics and Communications     Hybrid Journal   (Followers: 8, SJR: 0.42, CiteScore: 2)
African J. of Emergency Medicine     Open Access   (Followers: 6, SJR: 0.296, CiteScore: 0)
Ageing Research Reviews     Hybrid Journal   (Followers: 11, SJR: 3.671, CiteScore: 9)
Aggression and Violent Behavior     Hybrid Journal   (Followers: 457, SJR: 1.238, CiteScore: 3)
Agri Gene     Hybrid Journal   (Followers: 1, SJR: 0.13, CiteScore: 0)
Agricultural and Forest Meteorology     Hybrid Journal   (Followers: 17, SJR: 1.818, CiteScore: 5)
Agricultural Systems     Hybrid Journal   (Followers: 31, SJR: 1.156, CiteScore: 4)
Agricultural Water Management     Hybrid Journal   (Followers: 42, SJR: 1.272, CiteScore: 3)
Agriculture and Agricultural Science Procedia     Open Access   (Followers: 4)
Agriculture and Natural Resources     Open Access   (Followers: 3)
Agriculture, Ecosystems & Environment     Hybrid Journal   (Followers: 57, SJR: 1.747, CiteScore: 4)
Ain Shams Engineering J.     Open Access   (Followers: 5, SJR: 0.589, CiteScore: 3)
Air Medical J.     Hybrid Journal   (Followers: 6, SJR: 0.26, CiteScore: 0)
AKCE Intl. J. of Graphs and Combinatorics     Open Access   (SJR: 0.19, CiteScore: 0)
Alcohol     Hybrid Journal   (Followers: 12, SJR: 1.153, CiteScore: 3)
Alcoholism and Drug Addiction     Open Access   (Followers: 11)
Alergologia Polska : Polish J. of Allergology     Full-text available via subscription   (Followers: 1)
Alexandria Engineering J.     Open Access   (Followers: 1, SJR: 0.604, CiteScore: 3)
Alexandria J. of Medicine     Open Access   (Followers: 1, SJR: 0.191, CiteScore: 1)
Algal Research     Partially Free   (Followers: 10, SJR: 1.142, CiteScore: 4)
Alkaloids: Chemical and Biological Perspectives     Full-text available via subscription   (Followers: 2)
Allergologia et Immunopathologia     Full-text available via subscription   (Followers: 1, SJR: 0.504, CiteScore: 1)
Allergology Intl.     Open Access   (Followers: 5, SJR: 1.148, CiteScore: 2)
Alpha Omegan     Full-text available via subscription   (SJR: 3.521, CiteScore: 6)
ALTER - European J. of Disability Research / Revue Européenne de Recherche sur le Handicap     Full-text available via subscription   (Followers: 10, SJR: 0.201, CiteScore: 1)
Alzheimer's & Dementia     Hybrid Journal   (Followers: 51, SJR: 4.66, CiteScore: 10)
Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring     Open Access   (Followers: 4, SJR: 1.796, CiteScore: 4)
Alzheimer's & Dementia: Translational Research & Clinical Interventions     Open Access   (Followers: 4, SJR: 1.108, CiteScore: 3)
Ambulatory Pediatrics     Hybrid Journal   (Followers: 6)
American Heart J.     Hybrid Journal   (Followers: 53, SJR: 3.267, CiteScore: 4)
American J. of Cardiology     Hybrid Journal   (Followers: 56, SJR: 1.93, CiteScore: 3)
American J. of Emergency Medicine     Hybrid Journal   (Followers: 44, SJR: 0.604, CiteScore: 1)
American J. of Geriatric Pharmacotherapy     Full-text available via subscription   (Followers: 10)
American J. of Geriatric Psychiatry     Hybrid Journal   (Followers: 14, SJR: 1.524, CiteScore: 3)
American J. of Human Genetics     Hybrid Journal   (Followers: 34, SJR: 7.45, CiteScore: 8)
American J. of Infection Control     Hybrid Journal   (Followers: 29, SJR: 1.062, CiteScore: 2)
American J. of Kidney Diseases     Hybrid Journal   (Followers: 35, SJR: 2.973, CiteScore: 4)
American J. of Medicine     Hybrid Journal   (Followers: 47)
American J. of Medicine Supplements     Full-text available via subscription   (Followers: 3, SJR: 1.967, CiteScore: 2)
American J. of Obstetrics and Gynecology     Hybrid Journal   (Followers: 223, SJR: 2.7, CiteScore: 4)
American J. of Ophthalmology     Hybrid Journal   (Followers: 66, SJR: 3.184, CiteScore: 4)
American J. of Ophthalmology Case Reports     Open Access   (Followers: 5, SJR: 0.265, CiteScore: 0)
American J. of Orthodontics and Dentofacial Orthopedics     Full-text available via subscription   (Followers: 6, SJR: 1.289, CiteScore: 1)
American J. of Otolaryngology     Hybrid Journal   (Followers: 25, SJR: 0.59, CiteScore: 1)
American J. of Pathology     Hybrid Journal   (Followers: 28, SJR: 2.139, CiteScore: 4)
American J. of Preventive Medicine     Hybrid Journal   (Followers: 28, SJR: 2.164, CiteScore: 4)
American J. of Surgery     Hybrid Journal   (Followers: 38, SJR: 1.141, CiteScore: 2)
American J. of the Medical Sciences     Hybrid Journal   (Followers: 12, SJR: 0.767, CiteScore: 1)
Ampersand : An Intl. J. of General and Applied Linguistics     Open Access   (Followers: 7)
Anaerobe     Hybrid Journal   (Followers: 4, SJR: 1.144, CiteScore: 3)
Anaesthesia & Intensive Care Medicine     Full-text available via subscription   (Followers: 63, SJR: 0.138, CiteScore: 0)
Anaesthesia Critical Care & Pain Medicine     Full-text available via subscription   (Followers: 18, SJR: 0.411, CiteScore: 1)
Anales de Cirugia Vascular     Full-text available via subscription  
Anales de Pediatría     Full-text available via subscription   (Followers: 3, SJR: 0.277, CiteScore: 0)
Anales de Pediatría (English Edition)     Full-text available via subscription  
Anales de Pediatría Continuada     Full-text available via subscription  
Analytic Methods in Accident Research     Hybrid Journal   (Followers: 5, SJR: 4.849, CiteScore: 10)
Analytica Chimica Acta     Hybrid Journal   (Followers: 42, SJR: 1.512, CiteScore: 5)
Analytical Biochemistry     Hybrid Journal   (Followers: 185, SJR: 0.633, CiteScore: 2)
Analytical Chemistry Research     Open Access   (Followers: 12, SJR: 0.411, CiteScore: 2)
Analytical Spectroscopy Library     Full-text available via subscription   (Followers: 12)
Anesthésie & Réanimation     Full-text available via subscription   (Followers: 2)
Anesthesiology Clinics     Full-text available via subscription   (Followers: 23, SJR: 0.683, CiteScore: 2)
Angiología     Full-text available via subscription   (SJR: 0.121, CiteScore: 0)
Angiologia e Cirurgia Vascular     Open Access   (Followers: 1, SJR: 0.111, CiteScore: 0)
Animal Behaviour     Hybrid Journal   (Followers: 205, SJR: 1.58, CiteScore: 3)

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Journal Cover
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Journal Prestige (SJR): 0.814
Citation Impact (citeScore): 1
Number of Followers: 21  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0168-9002
Published by Elsevier Homepage  [3157 journals]
  • Wigner–Eckart theorem and the false EDM of 199Hg
    • Abstract: Publication date: Available online 11 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): W. Klassen, J.W. Martin, G. Pignol In neutron electric dipole moment experiments, 199Hg is used as a comagnetometer. The comagnetometer suffers from a false EDM arising in leading order from a gradient ∂Bz∕∂z in the magnetic field. Our work concerns higher-order multipole corrections to the false EDM of 199Hg. We show that for spherical traps, all higher-order multipole are identically zero. We further show that for the usual cylindrical traps used in EDM experiments, selection of quasi-spherical dimensions for the trap can reduce the higher-order contributions. The results are another indication that trap geometry is an important consideration for experiments desiring to control this systematic effect.
       
  • Improving light yield measurements for low-yield scintillators
    • Abstract: Publication date: Available online 11 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): J.B. Cumming, S. Hans, M. Yeh Light power spectra are introduced as a new tool for relative light yield (LY) determinations. Light event spectra have commonly been used for this purpose. Theoretical background supporting this change is provided. It is shown that the derivative of a light power spectrum can provide a reliable LY measurement at levels as low as 2% of those for high-yield liquid scintillators. Applications to light evolution in the PPO+LAB system and to water-based liquid scintillators are described.
       
  • Effects of temporary fogging and defogging in plastic scintillators
    • Abstract: Publication date: Available online 11 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Matthew Loyd, Matheus Pianassola, Charles Hurlbut, Kyle Shipp, L. Sideropoulos, Ken Weston, Merry Koschan, Charles L. Melcher, Mariya Zhuravleva Recent studies have shown that under certain environmental conditions, plastic scintillators which are used in a variety of applications in outdoor environments develop defects called “fogging”, resulting in a reduced useful lifetime and increased maintenance cost. Applications of plastic scintillators include scanning recycled steel going into a processing plant, personnel portals to scan employees, and scanning cargo and cars crossing borders of many countries. In this report, fogging was studied in conventional PVT and PS-based plastic scintillators, both field aged and freshly cast. A new fogging-resistant PVT-based formulation developed by scientists at Lawrence Livermore National Laboratory (LLNL) was tested as well. We used accelerated aging experiments via temperature and humidity cycling in controlled laboratory conditions to create observable temporary fogging defects in small samples (≤1 in3). Photoluminescence and optical transmission studies were used to evaluate the effect of the fogging. The time evolution of the induced temporary fogging formation and defogging (i.e. fading of defects in ambient conditions over time) were recorded using optical microscopy, time-lapse photography, and gravimetric analysis.
       
  • F R E Y A  for+spontaneous+fission&rft.title=Nuclear+Instruments+and+Methods+in+Physics+Research+Section+A:+Accelerators,+Spectrometers,+Detectors+and+Associated+Equipment&rft.issn=0168-9002&rft.date=&rft.volume=">Parameter optimization and uncertainty analysis of F R E Y A  for
           spontaneous fission
    • Abstract: Publication date: 1 April 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Volume 922Author(s): J. Van Dyke, L.A. Bernstein, R. Vogt In this paper we report on an effort to determine an optimal parameter set for the complete event fission model FREYA to reproduce spontaneous fission of 252Cf(sf), 244Cm(sf), 238Pu(sf), 240Pu(sf), 242Pu(sf), and 238U(sf). Earlier studies have partially optimized the event-by-event fission model FREYA with respect to the available experimental data using brute force computational techniques. We have confirmed and expanded these results using a least-squares minimization based on the simulated annealing approach. We have also developed a more complete statistical picture of this optimization, consisting of a full correlation matrix for the parameters utilized by FREYA. The newly improved parameter values themselves, along with this correlation matrix, have led to a more well-developed physical picture of the fission process.
       
  • Neutron spectroscopy and spectral unfolding with  4He fast
           neutron scintillators
    • Abstract: Publication date: 1 April 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Volume 922Author(s): Yinong Liang, Ting Zhu, Cody E. Parker, Andrea L. Richard, Thomas N. Massey, Rico Chandra, Heather Ray, Kelly A. Jordan, James Baciak, Andreas Enqvist Time-of-flight measurements were performed to determine the 4He pressurized fast neutron scintillation detectors response function and the ability of the detectors to be applied as a spectrometer. An experimentally validated neutron energy response function was used in conjunction with an iterative least squares unfolding technique to unfold a 252Cf spontaneous fission spectrum, a PuBe (α, n) spectrum, and a deuterium–deuterium (D–D) fusion reaction spectrum. The ability of the detectors to retain incident neutron energies makes them suitable for applications such as nuclear non-proliferation and spent nuclear fuel monitoring.
       
  • Development of a high resolution LaGPS imaging detector with pulse shape
           discrimination capability of different types of radiations
    • Abstract: Publication date: 1 April 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Volume 922Author(s): Seiichi Yamamoto, Kei Kamada, Shunsuke Kurosawa, Akira Yoshikawa Ce doped (Gd,La)2Si2O7 (LaGPS) is a new scintillator which has high light output and is a promising candidate for high resolution radiation imaging detectors. Thus we developed a radiation imaging detector using a LaGPS plate combined with a position sensitive photomultiplier tube (PSPMT) and evaluated the performance. We found that the decay times of LaGPS were different with the types of radiations and the separations of the images of the different types of radiations were possible using pulse shape discrimination. The spatial resolution for Am-241 alpha particles (5.5 MeV) was better than 0.31 mm FWHM and the energy resolution was 11 % FWHM. The spatial resolution for Sr–Y-90 beta particles was ∼0.6 mm FWHM and those for Co-57 gamma photons (122 keV) and Cs-137 X-ray (∼35 keV) were better than 0.6 mm FWHM and ∼0.8 mm FWHM, respectively. The decay times for alpha particles, beta particles, and gamma photons were 143 ns, 124 ns, and 119 ns, respectively. With these different decay times, the separation of alpha particles and gamma photons or beta particles was possible using the pulse shape discrimination. We conclude that the developed LaGPS imaging detector has high resolution for all types of radiations and is also capable of the simultaneous imaging and separating the different types of radiations.
       
  • Associated particle imaging instrumentation for future planetary surface
           missions
    • Abstract: Publication date: 1 April 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Volume 922Author(s): M.L. Litvak, Y.N. Barmakov, S.G. Belichenko, R.R. Bestaev, E.P. Bogolubov, A.V. Gavrychenkov, A.S. Kozyrev, I.G. Mitrofanov, A.V. Nosov, A.B. Sanin, V.N. Shvetsov, D.I. Yurkov, V.I. Zverev We have conducted ground tests to study the applicability of the Tagged Neutrons Method/Associated Particle Imaging methodology (TNM/API) for the making precise gamma ray spectroscopic measurements onboard lander missions to the Solar system planets. Our analysis was focused on the requirement to distinguish between the spacecraft background and the subsurface signal so as to correctly evaluate the elemental composition of planetary soils. The measurements were performed in a configuration where the gamma spectrometer was surrounded by significant amounts of material that imitated a spacecraft structure. It was found that the TNM/API can substantially suppress the spacecraft background and identify the true intensities of the gamma lines attributed to major soil elements such as O, Na, Mg, Al, Si and Fe and evaluate their concentrations with an accuracy of 2–10%.
       
  • Gamma–gamma angular correlation analysis techniques with the GRIFFIN
           spectrometer
    • Abstract: Publication date: 1 April 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Volume 922Author(s): J.K. Smith, A.D. MacLean, W. Ashfield, A. Chester, A.B. Garnsworthy, C.E. Svensson Gamma–gamma angular correlation measurements are a powerful tool for identifying the angular momentum (spin) of excited nuclear states involved in a γ-ray cascade, and for measuring the multipole orders and mixing ratios of transitions. Though the physical angular correlations are fully calculable from first principles, experimental effects can make the extraction of coefficients and thus conclusions about spins and mixing ratios difficult. In this article we present data analysis techniques developed for the clover detectors of the GRIFFIN spectrometer at TRIUMF-ISAC combined with GEANT4 simulations in order to extract accurate experimental results.
       
  • Statistical significance of CP violation in long baseline neutrino
           experiments
    • Abstract: Publication date: 21 March 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Volume 921Author(s): Walter Toki, Thomas W. Campbell, Erez Reinherz-Aronis The p-value or statistical significance of a CP conservation null hypothesis test is determined from counting electron neutrino and antineutrino appearance oscillation events. The statistical estimates include cases with background events and different data sample sizes, graphical plots to interpret results and methods to combine p-values from different experiments. These estimates are useful for optimizing the search for CP violation with different amounts of neutrino and antineutrino beam running, comparing results from different experiments and for simple cross checks of more elaborate statistical estimates that use likelihood fitting of neutrino parameters.
       
  • Effect of CsI(Tl) micro-conical-frustums on the performance of the
           pixelated CsI(Tl) scintillation screen in X-ray imaging
    • Abstract: Publication date: 21 March 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Volume 921Author(s): Hui Chen, Mu Gu, Xiaolin Liu, Juannan Zhang, Shiming Huang, Bo Liu, Chen Ni The pixelated CsI(Tl) scintillation screen based on oxidized silicon micro-pore array template with CsI(Tl) micro-conical-frustums (CMCF) was proposed. The effect of the CMCF on the performance of the pixelated CsI(Tl) scintillation screen in X-ray imaging was studied by using Geant4 Monte Carlo simulation code. The variations of the light output (LO), modulation transfer function (MTF) and detective quantum efficiency (DQE) for the screen with the cone angle β of the CMCF in X-ray imaging were revealed. The results show that the LO of the pixelated scintillation screen with CMCF is superior to that of the screens with CsI(Tl) micro-cylinders (CMC) or with reversed CsI(Tl) micro-conical-frustums (RCMCF), but the spatial resolution of the X-ray imaging system by using the pixelated scintillation screen with RCMCF is better than that by using the screens with CMCF or with CMC. At low frequency, the cone angle β corresponding to DQEs from good to bad are 2.40°, 0.00°and -2.40°. But at high frequency, the cone angle β corresponding to DQEs from good to bad change to 2.40°, -2.40°and 0.00°. The reason is that, for a pixelated scintillation screen, the DQE for the screen not only depends on the efficiency of X-ray absorption, but also depends on the number of scintillation photons exiting the bottom the screen per interacting X-ray photon and its Poisson excess, and MTF. The simulated results of DQEs show that the comprehensive performance of the pixelated CsI(Tl) screen with CMCF in X-ray imaging is better than that of the screens with CMC or with CRMCF.
       
  • Characterization of high purity germanium point contact detectors with low
           net impurity concentration
    • Abstract: Publication date: 21 March 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Volume 921Author(s): S. Mertens, A. Hegai, D.C. Radford, N. Abgrall, Y.-D. Chan, R.D. Martin, A.W.P. Poon, C. Schmitt High Purity germanium point-contact detectors have low energy thresholds and excellent energy resolution over a wide energy range, and are thus widely used in nuclear and particle physics. In rare event searches, such as neutrinoless double beta decay, the point-contact geometry is of particular importance since it allows for pulse-shape discrimination, and therefore for a significant background reduction. In this paper we investigate the pulse-shape discrimination performance of ultra-high purity germanium point contact detectors. It is demonstrated that a minimal net impurity concentration is required to meet the pulse-shape performance requirements.
       
  • Predictive model of scintillator plastic fogging in portals
    • Abstract: Publication date: Available online 11 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Stephen Payne, Natalia Zaitseva, Nicholas Myllenbeck, Richard Kouzes, Michael Lance, Alan Janos We have developed a science-based predictive model for fogging of the scintillator plastics deployed in radiation portal monitors. The only input required is the weather conditions [i.e., daily high and low, for temperature and relative humidity (R.H.)]. The code utilizes this information, together with a thermodynamic model of the water content in equilibrium with the plastic surface, a diffusion model of the water transport into the interior of scintillator plastic panel, and a comparison of the resulting paired “water-content/night-temperature” points as a function of position in the panel against an empirical “fog-line” that establishes a water/temperature criterion for the onset of fogging. We have analyzed the behavior of several representative portal monitor sites, and the output of the model analysis is reasonably consistent with observation.
       
  • Single photon detection with SiPMs irradiated up to 1014 cm−2
           1-MeV-equivalent neutron fluence
    • Abstract: Publication date: Available online 11 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): M. Calvi, P. Carniti, C. Gotti, C. Matteuzzi, G. Pessina Silicon photomultipliers (SiPM) are solid state light detectors with sensitivity to single photons. Their use in high energy physics experiments, and in particular in ring imaging Cherenkov (RICH) detectors, is hindered by their poor tolerance to radiation. At room temperature the large increase in dark count rate makes single photon detection practically impossible already at 1011 cm−2 1-MeV-equivalent neutron fluence. The neutron fluences foreseen by many subdetectors to be operated at the high luminosity LHC range up to 1014 cm−2 1-MeV-equivalent. In this paper we present the effects of such high neutron fluences on Hamamatsu and SensL SiPMs of different cell size. The advantage of annealing at high temperature (up to 175 ∘C) is discussed. We demonstrate that, after annealing, operation at the single photon level with a SiPM irradiated up to 1014 cm−2 1-MeV-equivalent neutron fluence is possible at cryogenic temperature (77 K) with a dark count rate below 1 kHz.
       
  • Front-end electronics of the Compact High Energy Camera
    • Abstract: Publication date: Available online 11 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): S.A. Leach, J.S. Lapington, D. Ross, J. Thornhill, C. Duffy, S. Funk, A. Zink, D. Jankowsky, R. White, J. Zorn, L. Tibaldo, G. Varner, A. Okumura, H. Tajima, J. Watson The Compact High Energy Camera is a focal plane camera designed for two mirror Schwarzschild-Couder design imaging air Cherenkov telescopes such as the SST-2M variants on the Cherenkov Telescope Array. It utilises a 2048-pixel array of silicon photomultipliers arranged in thirty-two 8 x 8 pixel2 tiles. Each detector tile is instrumented with a front-end electronics module designed to provide single photon counting with sub-nanosecond timing, full-waveform digitisation and event triggering capabilities based around TARGET ASICs. Performance results including triggering, digitiser noise, signal crosstalk, linearity and dynamic range from initial laboratory tests have been collated and are presented.
       
  • Editorial
    • Abstract: Publication date: Available online 11 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Robert Klanner, Fabio Sauli
       
  • Evaluation of covariant behavior of experimental quantities through
           statistical analysis of matched pairs of pulse height data
    • Abstract: Publication date: Available online 10 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Ramkumar Venkataraman, Stephen Croft, Tom Burr Understanding and proper treatment of correlated information is very important in measurement science because it is a common problem. Covariance, if unrecognized or ignored without justification, can lead to errors. Correlations can be introduced in many ways. Measurement procedures, assumptions, algorithms, operators, nuclear data, model mismatch, and many other factors including physical variables such as environmental conditions can introduce co-dependences. In the current work, the correlation between a pair of measured data, namely, the full energy or photo-peak (FEP) and the background continuum under the peak, will be evaluated. Pulse height spectra were acquired using a high-purity germanium spectrometer and multiple uranium enrichment standards supplied by New Brunswick Laboratories. The uranium enrichment standards that were measured were Certified Reference Materials (CRM) with 235U fractional abundances ranging from 0.32 at.% to 93.23 at.%. The measurements were performed under near-ideal conditions, taking precautions to minimize sources of systematic uncertainties. Under fixed geometrical measurement conditions, the uranium enrichment, in atom fraction, of an optically thick chemical compound is directly proportional to the intensity of a gamma-ray of a given energy (e.g., 185.7 keV) emitted directly following decay of 235U and emerging from the sample. The objectives of the measurement were to acquire high-quality spectra that can be used to construct an “enrichment meter” calibration, and to utilize the FEP ratios to evaluate limitations in the knowledge of the branching ratios of gamma lines emitted by uranium isotopes. Propagation of uncertainties and evaluation of covariances were of utmost concern in this work. Using a three region of interest (ROI) peak analysis method, FEP areas and continuum counts under the FEP were estimated from the gamma-ray spectra. The FEP and continuum under the FEP are an associated pair of random variables because they are measured simultaneously (refer to the same measurement interval) and further are derived from the same pulse height spectrum. For a given measurement, the two random variables are expected to be correlated because of various factors. In addition, under well-shielded conditions and for pure compounds, a large part of the continuum under the FEP under the relatively lower energy gamma-ray peaks from 235U is expected to be due to down-scattered higher energy gamma rays emitted by 238U daughters. The 238U abundance goes down (up) as enrichment goes up (down), so it is natural to ask to what degree the FEP and the continuum under FEP are correlated. This work examines this question experimentally, for a given measurement item measured during a given measurement campaign, by acquiring a series of spectra close in time so that the sample linear correlation coefficient can be computed. For each of the eight uranium CRM standards, covariant behavior of FEP and continuum data from prominent gamma lines emitted by 235U (143.76, 185.715, and 205.315 keV) were evaluated directly through statistical analysis of the matched data pairs.
       
  • Conceptual design of an orphan gamma source finder
    • Abstract: Publication date: Available online 10 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Ali Farzanehpoor Alwars, Faezeh Rahmani In this paper, a conceptual design of a gamma finder including four identical NaI (Tl) cylindrical scintillation detectors has been presented. This gamma finder can determine the position and the energy (in the energy range of 35 keV to 3 MeV) of an orphan gamma-ray point source in a limited space such as a treatment room or industrial lab. The novelty of this work is the ability to determine the activity of the source without directly using the efficiency calibration data. Being lightweight (portable), precision of 5° in determining angular position, error less than 10% in distance estimation, and suitable precision in calculating activity are the features of this system. Effects of walls and floor in a typical room (for considering backscattered gamma-rays) and the height shift of a source from the plane of array in different cases have been studied. Whole procedure has been based on the net counting rate of photopeak in gamma spectrum, so it can be applied for different energies as well. All aspects of this design have been simulated in presence of a 137Cs point source with MCNPX2.6 code.
       
  • Variable-energy isochronous accelerator with cotangential orbits for
           proton beam therapy
    • Abstract: Publication date: Available online 10 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Chishin Hori, Takamichi Aoki, Takayoshi Seki We have devised a new isochronous accelerator for proton beam therapy, which can control beam energy from 70 MeV to 235 MeV without using degraders. A feature of this accelerator is that the equilibrium orbits are cotangential, the same as for the classical microtron. This configuration of orbits leads to a small turn separation region on one side and a large turn separation region on the opposite side. Each beam between 70 MeV and 235 MeV is kicked by a massless septum installed in the large turn separation region, and it is extracted from the vicinity of the small turn separation region. Here we show an optical design of this accelerator, which is based on and extended from the hard edge model of azimuthally varying field cyclotrons. We found that the maximum and minimum magnetic fields are 2.45 T and 0.83 T, respectively, turn separation between 70 MeV and 235 MeV in the small turn separation region is 12.4 mm, and horizontal and vertical tunes over 10 MeV are between 1.0 and 1.5 and between 0.5 and 1.0, respectively. We calculated orbit deviations by a one-milliradian kick while varying the kick position and found that the large turn separation region is appropriate for installing the massless septum; this finding supports the consistency between the optical design and the extraction scheme.
       
  • Perovskite CsPbBr3 single crystal detector for alpha-particle
           spectroscopy
    • Abstract: Publication date: Available online 10 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Yihui He, Zhifu Liu, Kyle M. McCall, Wenwen Lin, Duck Young Chung, Bruce W. Wessels, Mercouri G. Kanatzidis Here we report the first spectroscopic alpha particle detection based on CsPbBr3 detectors with asymmetric contacts. The CsPbBr3 single crystal was grown from the melt using Bridgman method and then fabricated into detectors with different contacts. The In/CsPbBr3/Au detector presented a low dark current density (∼100 nA/cm2) and temporal stable performance under high electric field (1000 V/cm). Such detector demonstrated excellent gamma ray resolving capability with a full-width at half maximum (FWHM) of ∼5.9 keV for the 57Co 122 keV γ ray. The CsPbBr3 detector was capable of simultaneously resolving both the alpha particle (5.5 MeV) and γ ray (59.5 keV) peaks from 241Am radioactive isotope. The transport properties of CsPbBr3 were then determined based on the alpha particle spectra and corresponding rise time distributions. The equivalent values of electron and hole mobilities were indicated as 63 and 49 cm2/(V ⋅ s) respectively. The calculated electron and hole mobility-lifetime products were 4.5 × 10−4 and 9.5 × 10−4 cm2/V, respectively, demonstrating superior transport properties of holes over electrons in CsPbBr3. This work widens the scope of perovskite detectors to encompass charged radiation as well as high energy X/γ rays, and will significantly promote and guide further studies on perovskite materials for radiation detection applications.
       
  • Time Projection Chamber (TPC) detectors for nuclear astrophysics studies
           with gamma beams
    • Abstract: Publication date: Available online 9 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): M. Gai, D. Schweitzer, S.R. Stern, A.H. Young, R. Smith, M. Cwiok, J.S. Bihalowicz, H. Czyrkowski, R. Dabrowski, W. Dominik, A. Fijalkowska, Z. Janas, L. Janiak, A. Korgul, T. Matulewicz, C. Mazzocchi, M. Pfützner, M. Zaremba, D. Balabanski, I. Gheorghe Gamma-Beams at the HIγS facility in the USA and anticipated at the ELI-NP facility, now constructed in Romania, present unique new opportunities to advance research in nuclear astrophysics; not the least of which is resolving open questions in oxygen formation during stellar helium burning via a precise measurement of the 12C(α,γ) reaction. Time projection chamber (TPC) detectors operating with low pressure gas (as an active target) are ideally suited for such studies. We review the progress of the current research program and plans for the future at the HIγS facility with the optical readout TPC (O-TPC) and the development of an electronic readout TPC for the ELI-NP facility (ELITPC).
       
  • Development of proton beam irradiation system for small animals using FFAG
           accelerator
    • Abstract: Publication date: Available online 9 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): H. Tanaka, T. Takata, Y. Ishi, T. Uesugi, Y. Kuriyama, T. Watanabe, Y. Sakurai, S. Kawabata, S.-I. Masunaga, M. Suzuki To evaluate the biological effect of boron compounds on normal tissues in boron neutron capture therapy, it is necessary to compare the radiation effects of neutron irradiation and gamma ray irradiation on small animals in nonclinical studies. Neutron beams and gamma rays are difficult to collimate; thus, it is impossible to administer a dose on each part of the normal tissues of small animals. Therefore, we have developed a method to compare biological effects by irradiating neutrons and gamma rays after irradiating a proton beam to the point just before the threshold dose at which the biological effects occur. We aim to develop an irradiation field that irradiates proton beams locally using a fixed-field alternating-gradient (FFAG) accelerator and a small ridge filter.An aluminum scatterer, transmission dose monitor, ridge filter, range shifter, collimator, and a proton beam from the FFAG accelerator were used to form an irradiation field with a spread out Bragg peak (SOBP) with a length of 10 mm and a size of 10 mm2.Dose measurement was performed using a Gafchromic film and an ionization chamber. The irradiation system was simulated using the PHITS Monte Carlo simulation code, and simulation results were compared with experimental results.We succeeded in forming an irradiation field with a dose rate of 14.3 ± 0.24 Gy/min, an SOBP length of 10 mm, and a size of 10 mm2.
       
  • Advanced methods for the optical quality assurance of silicon sensors
    • Abstract: Publication date: Available online 9 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): E. Lavrik, I. Panasenko, H.R. Schmidt We describe a setup for optical quality assurance of silicon microstrip sensors. Pattern recognition algorithms were developed to analyze microscopic scans of the sensors for defects. It is shown that the software has a recognition and classification rate of > 90% for defects like scratches, shorts, broken metal lines etc. We have demonstrated that advanced image processing based on neural network techniques is able to further improve the recognition and defect classification rate.
       
  • γ -ray+coincidence+measurements&rft.title=Nuclear+Instruments+and+Methods+in+Physics+Research+Section+A:+Accelerators,+Spectrometers,+Detectors+and+Associated+Equipment&rft.issn=0168-9002&rft.date=&rft.volume=">An annular parallel plate avalanche counter for heavy-ion γ -ray
           coincidence measurements
    • Abstract: Publication date: Available online 8 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Akhil Jhingan, H.J. Wollersheim, R. Kumar, M. Saxena, R. Ahuja, M. Kumar, S. Dutt, N. Saneesh, T. Varughese, S.K. Mandal, P. Sugathan The characteristics and performance of an annular parallel plate avalanche counter (APPAC) developed for performing heavy ion nuclear physics experiments are presented. The main motive of developing this detector system is to perform Coulomb excitation (Coulex) experiments using particle-γ coincidence technique. The Coulex measurements are performed with APPAC and clover germanium detectors. The APPAC has a two electrode geometry and provides information about the scattering angles of the reaction products, which along with their velocity and/or energy information is used for correcting Doppler energy shift of γ-ray events coming from the in-flight decay of reaction products. The detector has an active area of ∼ 410 cm2 and provides scattering angle information in two coordinates namely polar angle θ and azimuthal angle ϕ. The ϕ resolution is fixed at 22.5°, and the θ resolution for the present experimental configuration is about 0.6°. Average rise times of the signals after amplification was observed to be 5 ns. During the experiments, the detector could handle heavy ion count rates of about 25 x 104 pps without any deterioration in the quality of signals.
       
  • Profile measurement of circulating electrons in a synchrotron by inserting
           a carbon wire
    • Abstract: Publication date: Available online 7 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Y. Obara, T. Ishikawa, H. Hama, F. Hinode, H. Kanda, S. Kashiwagi, M. Miyabe, T. Muto, K. Ozawa, H. Shimizu, A.O. Tokiyasu An internal radiator made of a carbon wire is employed to produce bremsstrahlung-photon beams for meson photoproduction experiments from circulating electrons in a synchrotron at the Research Center for Electron Photon Science, Tohoku University. The horizontal electron-beam size at the radiator location is determined from the decay rate of the resultant photon intensity as a function of the distance between the fixed position of the radiator and the centroid of the electron beam. The horizontal beam size at the radiator location is determined to be 0.74 mm with a statical error less than 0.01 mm for 1.3-GeV circulating electrons. The horizontal correlation between the position and momentum direction of the electron beam is also measured. The horizontal size and correlation are well-reproduced by the design values of the parameters of the synchrotron.
       
  • β +decay+of+244Am m,g &rft.title=Nuclear+Instruments+and+Methods+in+Physics+Research+Section+A:+Accelerators,+Spectrometers,+Detectors+and+Associated+Equipment&rft.issn=0168-9002&rft.date=&rft.volume="> β − decay of 244Am m,g
    • Abstract: Publication date: Available online 7 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): R. Tripathi, T.N. Nag, S. Sodaye, A. Bhattacharyyaa, P.K. Pujari Decay of 244Amm,g, produced by neutron irradiation of 243Am, has been studied by singles and coincidence measurements of decay γ rays. Two new γ rays of energy 940.54 ± 0.08 and 983.46 ± 0.08 keV have been observed in the decay of 244Amm which suggests a new level of 983.5 keV in 244Cm. This level has been assigned a tentative spin of (1−). In the present studies, uncertainties in the γ-ray intensities of 244Amm,g have been significantly reduced by nearly an order of magnitude for most of the γ rays. The data of half-lives have also been improved. More precise half-lives for 244Amm (T1∕2=26.13 ± 0.43 min) and 244Amg (T1∕2=600.4 ± 1.8 min) have been obtained.
       
  • Corrigendum to “Pendellösung interferometry by using pulsed
           neutrons”[Nucl. Instrum. Methods Phys. Res. A 908 (2018) 78–81]
    • Abstract: Publication date: Available online 6 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Shigeyasu Itoh, Masaya Nakaji, Yuya Uchida, Masaaki Kitaguchi, Hirohiko M. Shimizu
       
  • Cold electronics readout system for protoDUNE-SP LAr-TPC
    • Abstract: Publication date: Available online 6 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Hucheng Chen, Jack Fried, Shanshan Gao, Steve Kettell, Veljko Radeka, Maura Spanu, Elizabeth Worcester, Matthew Worcester, Bo Yu, Junbin Zhang The Single Phase (SP) TPC readout electronics are referred to as the “Cold Electronics (CE)” because they will operate in LAr, to minimize channel capacitance and noise by keeping the length of the connection between the anode wires and its corresponding electronics input to an absolute minimum. In this paper, the CE system and preliminary results from the CE testing at warm and cold conditions after their installation on the protoDUNE-SP detector are presented.
       
  • An innovative radiation hardened CAM architecture
    • Abstract: Publication date: Available online 6 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): O. Anagnostou, V. Liberali, M. Mews, S. Shojaii An innovative Content Addressable Memory (CAM) cell with radiation hardened (RH) architecture is presented. The RH-CAM is designed using a commercial 28 nm CMOS technology. The circuit has been simulated in worst-case conditions, and the effects due to single particles have been analyzed by injecting a current pulse into a circuit node. The proposed architecture is suitable for real-time pattern recognition tasks in harsh environments, such as front-end electronics in the ATLAS experiment at the Large Hadron Collider (LHC) and in space applications.
       
  • The DESY II test beam facility
    • Abstract: Publication date: Available online 5 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): R. Diener, J. Dreyling-Eschweiler, H. Ehrlichmann, I.M. Gregor, U. Kötz, U. Krämer, N. Meyners, N. Potylitsina-Kube, A. Schütz, P. Schütze, M. Stanitzki DESY Hamburg operates a test beam facility with three independent beam lines at the DESY II synchrotron. It is world-wide one of very few facilities providing test beams in the GeV range. To this end, it offers electron/positron beams with user-selectable momenta from 1-6 GeV/c. The available infrastructure for the users is unique, including a high field solenoidal magnet and permanently installed high-precision pixel beam telescopes. This publication gives a detailed description of the facility, the available infrastructure, and the simulated and measured performance.
       
  • Performance of Planacon MCP-PMT photosensors under extreme working
           conditions
    • Abstract: Publication date: Available online 5 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Yu.A. Melikyan, on behalf of ALICE collaboration The performance of the 25μm-pore Planacon MCP-PMT is discussed here and the device is evaluated for the use as the main photosensor of the Cherenkov arrays of the Fast Interaction Trigger (FIT) detector for the upgrade of the ALICE apparatus at the CERN LHC. During the LHC Run 3 and 4 FIT has to operate in strong magnetic fields and in large particle fluxes without significant ageing effects. The expected dynamic range for central modules of Cherenkov arrays of FIT is from 1 to ∼1000 MIPs. The required single-MIP time resolution is below 50 ps and the expected average repetition rate is 50 kHz. To fulfil these requests, the Planacon XP85012/A1-Q MCP-PMT has been customized into the XP85002/FIT-Q version. With the modified Planacon we were able to achieve a time resolution as low as 13 ps and ensure good timing of the device under the required dynamic range. A description of the implemented MCP-PMT modifications is presented here together with the outcome of the in-beam test of the assembled Cherenkov module and dedicated ageing- and magnetic field tests.
       
  • Sensitivity and linearity of optical fiber-based neutron detectors using
           small 6Li-based scintillators
    • Abstract: Publication date: Available online 4 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Akihisa Ishikawa, Atsushi Yamazaki, Kenichi Watanabe, Sachiko Yoshihashi, Akira Uritani, Kentaro Fukuda, Akifumi Koike, Ryo Ogawara, Mitsuru Suda, Tsuyoshi Hamano We developed optical fiber-based neutron detectors that use small pieces of 6Li-based scintillators, namely, Eu:LiCaAlF6 crystals and LiF/Eu:CaF2 eutectics. Considering that these elements have high light yields (more than 10,000 photons/neutron), they can produce pulse height spectra with clear peaks even when using optical fiber light guides. To adjust the neutron sensitivity, we controlled the amount of 6Li in the scintillator. We fabricated three different detectors using Eu:LiCaAlF6 and LiF/Eu:CaF2 with various amounts of 6Li and then evaluated the neutron sensitivity of each detector. This approach confirmed that there was a linear relationship between the neutron sensitivity and amount of 6Li, thus implying that the 6Li mass measured by a high-precision balance could be a good metric of neutron sensitivity. We also checked the linearity of the output of the detector at relatively high neutron fluxes by using an accelerator-based neutron source. Although the detectors showed saturation behavior at high count rate, we were able to cover a relatively wide dynamic range by combining multiple detectors using different amounts of 6Li. After correcting for the pulse height distortion and count loss due to pile-up events, we were able to confirm the linearity of the detectors up to a count rates of 100 kcps.
       
  • Very high energy astrophysics with the SHALON Cherenkov telescopes
    • Abstract: Publication date: Available online 6 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): V.G. Sinitsyna, V.Y. Sinitsyna, S.S. Borisov, A.I. Klimov, R.M. Mirzafatikhov, N.I. Moseiko The base of experiments used the imaging atmospheric Cherenkov telescopes is that the Cherenkov light emitted from the particles of extensive air shower created by the primary gamma-ray is collected by a mirror reflector and then detected by a pixelized PMT camera. SHALON are the imaging atmospheric Cherenkov telescopes created for the gamma-ray astronomy at the energies of 800 GeV to 100 TeV. Telescopes are located in the Tien-Shan mountains at the altitude of 3340 m a.s.l. The telescope systems have characteristics sufficient to record precise information about the shower structure in the energy range under consideration. SHALON experiment has been operating since 1992 and covers the wide astroparticle physics topics including an acceleration and origin of cosmic rays in supernova remnants, the physics of relativistic flaring objects like a black holes and active galactic nuclei as well as the long-term studies of the different type objects.
       
  • A review of the prompt neutron nu-bar value for 252Cf
           spontaneous fission
    • Abstract: Publication date: Available online 6 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Ramkumar Venkataraman, Stephen Croft, Andrea Favalli, Robert D. McElroy Jr. Passive neutron multiplicity counting can be used to determine the absolute emission rate of 252Cf spontaneous fission sources. Such sources can then be used to characterize and calibrate instruments used to assay Pu for materials control and accountancy, nuclear safeguards, and nuclear security applications. An important contribution determining the ultimate accuracy of this technique is how well the neutron multiplicity distribution of 252Cf is known (actually the low order factorial moments are typically used). This knowledge governs how well the emission rate of the 252Cf sources can be determined. Additionally, because 252Cf is used as a reference standard against which other spontaneously fissile systems are compared, it also governs the scaling of the 252Cf characterization and calibration data to the corresponding performance estimates for the spontaneously fissile Pu-nuclides. The main scale setting parameter is nu-bar, the average number of neutrons released following fission, of 252Cf. This is a fundamental nuclear constant.  In this work we briefly review the 14 high quality absolute determinations of nu-bar and subject them to a full covariance evaluation. This is compared to several variants of weighted mean, including an extension where an allowance is made for the uncertainty in the estimated variance on each point. The prompt nu-bar value was found to be robust to the different statistical assessment methods applied and moreover the overall uncertainty estimates were of similar magnitude. Based on the full covariance treatment a prompt nu-bar value of (3.7573 ± 0.0056) prompt neutron per fission was obtained, where the uncertainty is at the 1–σ level (68% confidence interval). This compares favorably with the value of Zucker and Holden, (3.757 ± 0.010) prompt neutrons per fission, long used in the nuclear safeguards community. The relative standard deviation of 0.15% obtained from the analysis reported here is sufficiently small that we advocate for a new high accuracy determination of the delayed neutron contribution, since this is needed to correct the Mn-bath class of nu-bar measurements. Collectively the measurements span the period 1963 to 1985. Of the 14 measurements six carry very little weight (individually 2% or less), five carry intermediate weight (individually 3%–7%), while three values are highly weighted (individually 15%–32%). These have reported relative standard deviations of between 0.2% and 0.3%. Given the small number of measurements with small reported uncertainties, and the fact that the youngest such determination is over 30 years old, we also strongly suggest that new measurements of the highest currently achievable quality are needed. In this regard a high efficiency 3He based counter would remove the residual concern over γ-sensitivity of doped liquid scintillator tank data.
       
  • Design of the cold and thermal neutron moderators for the European
           Spallation Source
    • Abstract: Publication date: Available online 6 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): L. Zanini, K.H. Andersen, K. Batkov, F. Mezei, A. Takibayev, E.B. Klinkby, T. Schönfeldt At the European Spallation Source (ESS), neutrons will be generated by spallation induced by a 2-GeV proton beam on a tungsten target. ESS will have a grid of 42 beamports available for a variety of neutron scattering experiments. Neutron moderators will provide thermal and cold neutrons to the instruments, allowing bispectral beam extraction wherever needed.The moderators were designed by adopting a holistic design approach that has considered brightness, brightness transfer and beam extraction constraints, resulting in a system with the following main features: low-dimensional moderators for enhanced brightness and maximum flux to the sample; a single moderator system placed above the spallation target; lateral shape of the moderators optimized for bispectral extraction. A moderator with a vertical extraction surface of 3 cm was chosen as result of the optimization process.With all initial instruments pointing to the top moderator, and a beamport system that allows the possibility to extract neutrons from above and below the target, the adopted configuration opens the possibility to have different types of moderators below the target, so that other neutron beams of different intensity, or spectral shape, with respect to the ones delivered by the top moderator, could be envisaged, adding additional scientific opportunities to the facility without having the need to build a second target station.
       
  • Radon detection using alpha scintillation KACST cell
    • Abstract: Publication date: Available online 4 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Ayman M. Abdalla, Atif M. Ali, Mohamed Al-Jarallah, Go Okada, Noriaki Kawaguchi, Takayuki Yanagida Features of a high-efficiency Radon cell with native scintillator were presented experimentally. In this work, we report the scintillation characteristics of Ag activated ZnS nanoparticle scintillator. Pulse height spectrum (PHS) of 241Am 5.48 MeV α-particles and 60 KeV γ rays has been measured using the prepared scintillator. After the optimization, the cell has been painted with the native scintillator. The cell qualities which include the sensitivity and efficiency are guaranteed for Radon detection. Results of native scintillator fabrication and characterization, along with radon cell calibration and application are also addressed and thoroughly discussed. The cell demonstrating as a scintillation detector for radon gas detection.
       
  • Development of low radioactivity photomultiplier tubes for the XMASS-I
           detector
    • Abstract: Publication date: Available online 4 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): K. Abe, K. Hiraide, K. Ichimura, Y. Kishimoto, K. Kobayashi, M. Kobayashi, S. Moriyama, M. Nakahata, T. Norita, H. Ogawa, K. Sato, H. Sekiya, O. Takachio, A. Takeda, S. Tasaka, M. Yamashita, B.S. Yang, N.Y. Kim, Y.D. Kim, Y. Itow XMASS-I is a single-phase liquid xenon detector whose purpose is direct detection of dark matter. To achieve the low background requirements necessary in the detector, a new model of photomultiplier tubes (PMTs), R10789, with a hexagonal window was developed based on the R8778 PMT used in the XMASS prototype detector. We screened the numerous component materials for their radioactivity. During development, the largest contributions to the reduction of radioactivity came from the stem and the dynode support. The glass stem was exchanged to the Kovar alloy one and the ceramic support were changed to the quartz one. R10789 is the first model of Hamamatsu Photonics K. K. that adopted these materials for low background purposes and provided a groundbreaking step for further reductions of radioactivity in PMTs. Measurements with germanium detectors showed 1.2 ± 0.3 mBq/PMT of 226Ra, less than 0.78 mBq/PMT of 228Ra, 9.1 ± 2.2 mBq/PMT of 40K, and 2.8 ± 0.2 mBq/PMT of 60Co. In this paper, the radioactive details of the developed R10789 are described together with our screening methods and the components of the PMT.
       
  • Development of a sub-miniature gamma camera for multimodal imaging system
    • Abstract: Publication date: Available online 4 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Young-Jun Jung, Sanggoo Jeong, Eungi Min, Minho Kim, Hakjae Lee, Yu Hua Quan, Jiyun Rho, Kyeong Min Kim, Hyun Koo Kim, Kisung Lee In the recent past, gamma-ray imaging detectors have achieved an intrinsic spatial resolution of less than 1 mm within a few centimeters of a useful field of view (UFOV). Unlike to conventional gamma cameras, which are large and heavy, the compact gamma-ray imaging detectors can improve the performances of the gamma cameras used in the various fields. In this study, we developed a sub-miniature gamma camera for a multimodal imaging system. The camera has a gamma-ray detector, miniature electronics modules, and a diverging hole collimator. The detector consisted of the sub-millimeter pixelated Ce:GAGG array and the silicon photomultiplier (SiPM) array module. We organized the miniature electronics modules according to the functions; an MPPC base board, analog signal processing board, integrated power supply board, and compact data acquisition (DAQ) base board. The diverging hole collimator widened an imaging area of the gamma camera from the UFOV of the detector. On the detector side, dimensions of each hole and septa were identical to the pixel and inter-pixel thickness of the reflector of scintillator array. For the intrinsic performance test, we acquired a flood map image of 729 (27 × 27) scintillator pixels, and the energy resolution was 18.9% for an integrated energy histogram of 99mTc (140 keV). For the extrinsic performance test, we used the 57Co sheet source, and made a 99mTc line source using a capillary tube. The sources located at 10 cm apart from the collimator surface. The imaging area was three times wider than the UFOV of the detector. The system sensitivity was 19 CPM/μCi and the spatial resolution was 3.5 mm. The usability of the proposed gamma camera will not be confined to existing applications due to its compactness and novelty.
       
  • SiC detectors for evaluation of laser-plasma dynamics employing gas-puff
           targets
    • Abstract: Publication date: Available online 4 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): A. Torrisi, P.W. Wachulak, H. Fiedorowicz, L. Torrisi An Nd:YAG pulsed laser was employed to irradiate different gas-puff targets. The interaction gives rise to the emission of soft X-ray (SXR), ultraviolet and extreme ultraviolet (EUV) radiation useful for X-ray microscopy. A Silicon Carbide (SiC) and a Si detector were employed to characterize the photon plasma emission of different gases in different wavelength ranges. The EUV and SXR measurements with different filters show the applicability of SiC detectors for plasma monitoring and characterization. Detector linearity, plasma evolution over the time and the relative intensity signal of both detectors will be presented and discussed.
       
  • Factors affecting performance of the micro-layered fast-neutron detector
    • Abstract: Publication date: Available online 3 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Priyarshini Ghosh, Wenkai Fu, Mark J. Harrison, Patrick K. Doyle, Jeremy A. Roberts, Douglas S. McGregor The Micro-Layered Fast-Neutron Detector (MLFD) is a proton-recoil scintillation detector constituting microscale alternating layers of hydrogenous medium and ZnS:Ag. The device employs a peripheral photon detection for maximizing light collection while minimizing gamma-ray background. The layered configuration offers several novel advantages inherently by design, e.g., it overcomes the light-opacity limitation of polycrystalline ZnS, recoil protons have a high probability of reacting with the scintillation grains in their forward-directional path, the design and photomultiplier orientation eliminates the need for extraneous light guides, and minimizes Ĉerenkov generation and collection. The most striking ability of the MLFD is that its efficiency can be scaled higher by simply adding layers and increasing the length, up to 20 cm. Presently, a 40-mm MLFD has an intrinsic detection efficiency of 9.2% for bare 252Cf. Described is a comparison between experimental results and a theoretical model, the respective performances of which differ in high energy regions. The differences in the two models suggest that epoxy in the MLFD contributes to an increased count rate in higher channels.
       
  • Status and perspectives of solid state photon detectors
    • Abstract: Publication date: Available online 3 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): S. Vinogradov, E. Popova Development of solid state photon detectors is a mature field of engineering and technology based on well-established grounds of solid state physics, and, in the same time, a frontier area of research and innovations faced with dramatic challenges.The ultimate challenge for the modern developments is a detection of optical signals at a quantum level – resolving arrival time and spatial location of individual photons – to realize a formula “every photon counts”. To succeed, the developments are focused on improvements in three directions: threshold sensitivity and photon number resolution, fast timing and time resolution, and fine granularity imaging with fast readout. There are many inherent trade-offs to be resolved in each direction.Development of Silicon Photomultiplier (SiPM) is considered as one of the most promising innovation toward “near ideal” photon detector. SiPMs of various designs have been developed in the 1990s–2000s in Russia, and their unique performance in the photon number and time resolution has been demonstrated and recognized in the mid-2000s. Now SiPMs are widely implemented in nuclear medicine, high energy physics, astrophysics, and Cherenkov light detection. However, developers of Geiger Mode APD or SPAD arrays based on active quenching also found new approaches and opportunities for considerable improvements using modern CMOS technology, namely: reduction of a dead space occupied by electronics, multiplexing readout architecture, backside illumination, and 3D integration of photosensor and electronic layers (3D digital SiPM). Detection of Cherenkov light is one of the most challenging application for photodetectors. Superior photon number resolution starting from single photons, picosecond-scale time resolution, and large-area imaging are typical requirements, and all these highly demanded capabilities are contradictory. This report presents overview and analysis of the state-of-art in the modern solid state photon detectors as well as their potential and perspectives to meet the quantum imaging challenge.Graphical abstractGraphical abstract for this article
       
  • SSPALS: A tool for studying positronium
    • Abstract: Publication date: Available online 3 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Adam Deller Single-shot positron annihilation lifetime spectroscopy (SSPALS) is an extremely useful tool for experiments involving the positronium atom (Ps). I examine some of the methods that are typically employed to analyze lifetime spectra, and use a Monte-Carlo simulation to explore the advantages and limitations these have in laser spectroscopy experiments, such as resonance-enhanced multiphoton ionization (REMPI) or the production of Rydberg Ps.
       
  • Background discrimination for neutrinoless double beta decay in liquid
           xenon using Cherenkov light
    • Abstract: Publication date: Available online 2 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Jason Philip Brodsky, Samuele Sangiorgio, Michael Heffner, Tyana Stiegler Neutrinoless double beta decays in liquid xenon produce a significant amount of Cherenkov light, with a photon number and angular distribution that distinguishes these events from common backgrounds. A GEANT4 simulation was used to simulate Cherenkov photon production and measurement in a liquid xenon detector and a multilayer perceptron was used to analyze the resulting distributions to classify events based on their Cherenkov photons. Our results show that a modest improvement in the sensitivity of neutrinoless double beta decay searches is possible using this technique, but the kinematics of the neutrinoless double beta decay and electron scattering in liquid xenon substantially limit this approach.
       
  • The PROSPECT reactor antineutrino experiment
    • Abstract: Publication date: Available online 2 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): J. Ashenfelter, A.B. Balantekin, C. Baldenegro, H.R. Band, C.D. Bass, D.E. Bergeron, D. Berish, L.J. Bignell, N.S. Bowden, J. Boyle, J. Bricco, J.P. Brodsky, C.D. Bryan, A. Bykadorova Telles, J.J. Cherwinka, T. Classen, K. Commeford, A. Conant, A.A. Cox, D. Davee The Precision Reactor Oscillation and Spectrum Experiment, PROSPECT, is designed to make both a precise measurement of the antineutrino spectrum from a highly-enriched uranium reactor and to probe eV-scale sterile neutrinos by searching for neutrino oscillations over meter-long baselines. PROSPECT utilizes a segmented 6Li-doped liquid scintillator detector for both efficient detection of reactor antineutrinos through the inverse beta decay reaction and excellent background discrimination. PROSPECT is a movable 4-ton antineutrino detector covering distances of 7 m to 13 m from the High Flux Isotope Reactor core. It will probe the best-fit point of the ν̄e disappearance experiments at 4 σ in 1 year and the favored regions of the sterile neutrino parameter space at more than 3σ in 3 years. PROSPECT will test the origin of spectral deviations observed in recent θ13 experiments, search for sterile neutrinos, and address the hypothesis of sterile neutrinos as an explanation of the reactor anomaly. This paper describes the design, construction, and commissioning of PROSPECT and reports first data characterizing the performance of the PROSPECT antineutrino detector.
       
  • Trigger and timing distributions using the TTC-PON and GBT bridge
           connection in ALICE for the LHC Run 3 Upgrade
    • Abstract: Publication date: Available online 2 January 2019Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Jubin Mitra, Erno David, Eduardo Mendez, Shuaib Ahmad Khan, Tivadar Kiss, Sophie Baron, Alex Kluge, Tapan Nayak The ALICE experiment at CERN is preparing for a major upgrade for the third phase of data taking run (Run 3), when the high luminosity phase of the Large Hadron Collider (LHC) starts. The increase in the beam luminosity will result in high interaction rate causing the data acquisition rate to exceed 3 TB/sec. In order to acquire data for all the events and to handle the increased data rate, a transition in the readout electronics architecture from the triggered to the trigger-less acquisition mode is required. In this new architecture, a dedicated electronics block called the Common Readout Unit (CRU) is defined to act as a nodal communication point for detector data aggregation and as a distribution point for timing, trigger and control (TTC) information. The ALICE trigger protocol in the upgraded triggerless readout architecture uses two asynchronous fast serial trigger links (FTLs) connections: the TTC-PON and the GBT. We have carried out a study to evaluate the quality of the embedded timing signals forwarded to the connected electronics using the TTC-PON and GBT bridge connection. We have used four performance metrics to characterize the communication bridge: (a) the latency added by the firmware logic, (b) the jitter cleaning effect of the PLL on the timing signal, (c) BER analysis for quantitative measurement of signal quality, and (d) the effect of optical transceivers parameter settings on the signal strength. Reliability study of the bridge connection in maintaining the phase consistency of timing signals is conducted by performing multiple iterations of power on/off cycle, firmware upgrade and reset assertion/de-assertion cycle (PFR cycle). The Intel® development kit having Arria® 10 FPGA is used for developing the prototype of the firmware. The test results are presented and discussed concerning the performance of the TTC-PON and GBT bridge communication chain and its compliance with the ALICE timing requirements.
       
  • Status of the GlueX DIRC
    • Abstract: Publication date: Available online 26 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): M. Patsyuk, A. Ali, F. Barbosa, J. Bessuille, E. Chudakov, R. Dzhygadlo, C. Fanelli, J. Frye, J. Hardin, A. Hurley, G. Kalicy, J. Kelsey, C. Schwarz, J. Schwiening, J. Stevens, M. Shepherd, W. Li, T. Whitlatch, M. Williams, Y. Yang This year we start assembling the DIRC detector to upgrade the particle identification capabilities in the forward region of the GlueX detector in Hall D at Jefferson Lab. The main components of the GlueX DIRC are the four bar boxes (reused from the decommissioned BaBar DIRC) and two photon cameras, which were designed based on the prototype for the SuperB FDIRC. The delicate bar boxes have already arrived at JLab from SLAC, where they have been stored for the last ten years. They will be attached to the newly built photon cameras and installed in Hall D already for the 2019 spring run. We present the status of the GlueX DIRC project including the ongoing R&D and the plan for the future.
       
  • The study of fast neutrons production via the electrodisintegration
           reactions of high energy electrons
    • Abstract: Publication date: Available online 26 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Yangyi Yu, Tongyuan Cui, Xiufeng Weng, Yuqi Yang, Zihan Zhang, Shuren Lin, Zhi Zhang, Yigang Yang The (e, n) reactions are studied in this paper to investigate the possibility of using it to produce ultra-short-pulse-width neutrons for the neutron resonance analysis. The research shows that electrons with higher energies will have larger (e, n) cross section, which may surpass the (γ, n) cross section if the energy is higher than 30 MeV. The (e, n) cross section for the 100 MeV electron and  181Ta nucleus is experimentally evaluated as 10.8 mb. An (e, n) neutron source realized with 100 MeV electrons and 0.6 mm  181Ta foil may achieve a FOM (figure of merit) factor higher than that of a (γ, n) neutron source, which can be realized with 100 MeV electrons and a  181Ta target with the typical thickness of 10 cm.
       
  • Plastic scintillators stable for operating in wide ranges of humidity and
           temperature variations
    • Abstract: Publication date: Available online 26 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): N.P. Zaitseva, A.N. Mabe, M.L. Carman, A.M. Glenn, J.W. Inman, S.A. Payne To provide efficient and reproducible response to nuclear radiation, scintillating plastics should be prepared as materials of high optical transparency and homogeneity that should remain intact during the lifetime of their operation. A problem with traditionally used polyvinyltoluene (PVT) or polystyrene (PS) plastic scintillators arises from their exposure to repeated large temperature swings that cause surface and volume defects, resulting in decreased sensitivity of the detection properties. The problem can be avoided by composition modifications that enable preparation of plastics with properties that are resistant to the continuous variations in environmental conditions. This paper describes improvements in physical properties that can be achieved by the addition of crosslinkers (such as divinylbenzene, DVB) and oxygen-containing compounds or copolymers (e.g. polymethylamethacrylate, PMMA) to the traditional PVT or PS polymer matrices. Results of characterization show that the new materials can be prepared with the scintillation performance equal to that of commercial plastic scintillators, such as EJ-200.
       
  • Improved manufacturing and performance of the dual-sided microstructured
           semiconductor neutron detector (DS-MSND)
    • Abstract: Publication date: Available online 26 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): T.R. Ochs, S.L. Bellinger, R.G. Fronk, L.C. Henson, R.M. Hutchins, D.S. McGregor Microstructured semiconductor neutron detectors (MSNDs) have shown to be a viable candidate for 3He detector replacements offering low cost, minimal power consumption, and high intrinsic thermal-neutron detection efficiency. MSNDs are vertically operated pνn-diodes with microfeatures etched into the semiconductor substrate that are subsequently backfilled with neutron conversion material. Charged particles emitted after a neutron is absorbed within an microfeature can interact in the adjacent semiconductor substrate, and those interactions can then be measured. Commercially produced MSNDs have an intrinsic thermal-neutron detection efficiency of approximately 30%. The dual-sided microstructured semiconductor neutron detector (DS-MSND) is a pνp-type diode, which implements microstructures on the back-side of a MSND that complement the front-side microstructures and eliminate neutron free streaming paths. The intrinsic thermal-neutron detection efficiency of DS-MSNDs was previously limited to less than 55%. The major limiting factor in detection efficiency of DS-MSNDs was determined to be the 6LiF powder packing fraction within the DS-MSND trenches. The packing fraction was previously assumed to be greater than 90%; however, recent measurements show the actual packing fraction was approximately 30%. MCNP6 simulations were performed with the updated packing fraction and showed good agreement with the detection efficiencies measures with the previous generation of detectors. A new backfilling method was developed that utilizes a mixture of two 6LiF powders with different powder particle size distributions. In the new method the powder is pressed into the DS-MSND trenches with a roller instead of using the centrifugal backfill method, which could remove previously backfilled material during the back-side trench filling centrifuge process. The new backfill method has improved the attainable 6LiF packing fraction to 55%. The new 6LiF backfilling method coupled an improved wet etching process have yielded DS-MSNDs with intrinsic thermal-neutron detection efficiencies as high as 69.2 ± 0.8%, which matched well with updated MCNP6 simulations.
       
  • Neutron absorption in supermirror coatings: Effects on shielding
    • Abstract: Publication date: Available online 26 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Rodion Kolevatov, Christian Schanzer, Peter Böni The quantification of the dose rate and the composition of the dose in the vicinity of supermirror coated guides is essential for designing shielding for beamlines transporting neutrons with a high flux. We present results on a calculation of radiative neutron absorption in Ni/Ti and NiMo/Ti supermirror coatings which leads to the emission of high energy gamma rays. A simple parameterization of the absorption probability in the coating materials per incident neutron is given as a function of momentum transfer at reflection.
       
  • Development of a solid-state position sensitive neutron detector prototype
           based on  6Li - glass scintillator and digital SiPM arrays
    • Abstract: Publication date: Available online 26 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): S. Kumar, M. Herzkamp, D. Durini, H. Nöldgen, S. van Waasen Photomultiplier tubes (PMT) have been used extensively as the photodetector of choice in scintillation based detectors for cold and thermal neutrons. However, the limitations of PMT based scintillation neutron detectors such as their sensitivity to magnetic fields or their high operating voltages (> 1 kV) have triggered the search for alternative photodetectors for these applications. Silicon photomultipliers (SiPM) operate in the single photon regime, have lower operating voltages (∼20–70 V) than PMTs and are insusceptible to magnetic field. Additional features of the SiPMs like their low production cost, compactness and higher readout rates make them a potential candidate to replace the photodetector part in these developments. Therefore, we are developing a scintillation neutron detector based on SiPM technology. The detector prototype with an active detection area of 13 cm × 13 cm is aimed to be used in the future at the TREFF instrument of the Heinz Maier-Leibnitz Zentrum (MLZ) in Garching, Germany, for neutron reflectometry experiments. In this paper, we report the detector concept, its development and the simulation results for design optimization.
       
  • Airglow monitoring by one-pixel detector
    • Abstract: Publication date: Available online 26 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Š. Mackovjak, P. Bobík, J. Baláž, I. Strhárský, M. Putiš, P. Gorodetzky The night time airglow is a dynamic phenomenon that acts as a background for the detection of the extensive air shower (EAS) fluorescence. It is a mandatory task to monitor this background for the ground-based telescopes and for the planned space-based telescopes, dedicated to observe the EAS events induced by the ultra-high energy cosmic rays. To perform this task, we have developed a one-pixel Airglow MONitor (AMON) instrument. This instrument provides the absolute intensities of the measured night sky background in the near-ultraviolet spectral range and in the one second temporal resolution. It is designed to be easily operated in different locations and so to offer required spatial resolution. The first results demonstrate that AMON data might be useful not only for the high-energy astrophysics purposes, but also for the studies of the airglow dynamics.
       
  • Pepperpot emittance measurements of ion beams from an electron beam ion
           source
    • Abstract: Publication date: Available online 26 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): J. Pitters, M. Breitenfeldt, S. Duarte Pinto, H. Pahl, A. Pikin, A. Shornikov, F. Wenander A pepperpot emittance meter was used to measure the transverse emittance of multiply charged beams from REXEBIS, an Electron Beam Ion Source (EBIS) used for charge breeding of radioactive ion beams. The emittance meter is equipped with a Micro Channel Plate (MCP), a phosphor screen and a CCD camera for detection of the ion signal. The pulsed beam structure of low duty cycle imposes challenging constraints on the detector settings. In this article we give a careful analysis of the optimal operating parameters of the pepperpot emittance meter for ion beams of varying intensities. Emittance values for mass-separated and non-separated beams for different operating modes of the EBIS are presented. Furthermore we report on aberrations created in our injection∕extraction system.
       
  • Radiation damage assessment of the sixth SINQ target irradiation program
           based on MCNPX simulation
    • Abstract: Publication date: Available online 25 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): D. Aulet, Y. Dai, R.M. Bergmann, M. Wohlmuther The 6th SINQ Target Irradiation Program (STIP VI) was conducted in SINQ Target 9 during 2011 and 2012. A radiation damage assessment based on a simulation using the MCNPX code was performed to obtain the irradiation parameters of displacement damage, helium and hydrogen concentrations in each specimen rod placed in the target.The gamma mapping performed on the proton beam entrance window after irradiation provided the proton fluence distribution used for implementing the source definition in the simulation. The proton and neutron fluences along the target as well as the energy deposition were calculated. Corresponding to the average beam current of 1.42 mA, the maximum neutron flux obtained is 5.95x1014 n/(cm2⋅ s) and the maximum energy deposition in the Zircaloy-2 cladding tubes is 568 W/(cm3⋅ mA). The irradiation parameters of selected materials in each specimen rod were calculated by multiplying the proton and neutron fluences with the corresponding cross section data. The maximum displacement damage was obtained for Zircaloy-2 in Row 2 with a value of 72.1 dpa (displacement per atom). The maximum helium concentration was obtained for tantalum in Row 1 with a value of 3630 appm and the maximum hydrogen concentration was obtained for tungsten in Row 1 with a value of 17590 appm. All these values are the highest for the corresponding materials ever reached in a spallation target irradiation environment. The helium concentrations are also the highest ever obtained in bulk specimens.
       
  • Fast neutron resonance radiography for elemental imaging
    • Abstract: Publication date: Available online 24 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): David Perticone, Brandon W. Blackburn, Gongyin Chen, Wilbur A. Franklin, Ernest E. Ihloff, Gordon E. Kohse, Richard C. Lanza, Brian McAllister, Vitaliy Ziskin We present experimental evidence supporting the technique of Fast Neutron Resonance Radiography (NRR). A set of neutron attenuation images collected at several different neutron energies are transformed into a set of elemental maps, indicating the presence and quantity of a fixed set of basis elements. Here we report on the construction, calibration, and results from a prototype NRR imaging system. We discuss the utility of elemental maps for automated detection of materials as well as standoff non-destructive classification of chemical compounds.
       
  • Measurements of the lifetime of orthopositronium in the LAB-based liquid
           scintillator of JUNO
    • Abstract: Publication date: Available online 24 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Mario Schwarz, Sabrina M. Franke, Lothar Oberauer, Miriam D. Plein, Hans Th.J. Steiger, Marc Tippmann Electron antineutrinos are detected in organic liquid scintillator based neutrino experiments by means of the inverse beta decay, producing both a positron and a neutron. The positron may form a bound state together with an electron, called positronium (Ps). The longer-lived spin state of Ps, orthopositronium (o-Ps) has a lifetime of about 3ns in organic liquid scintillators (LS). Its formation changes the time distribution of photon emission, which affects positron reconstruction algorithms and allows the application of pulse shape discrimination (PSD) to distinguish electron from positron events.In this work we measured the lifetime τ2 and formation probability I2 of o-Ps in the linear alkylbenzene (LAB) based LS of the JUNO (Jiangmen Underground Neutrino Observatory) experiment including wavelength shifters, obtaining τ2=2.98ns±0.05ns and I2=44%±3%. We are using a novel type of setup, which allows for additional means of background suppression compared to commonly used PALS (positron annihilation lifetime spectroscopy) measurement setups.
       
  • An analog-to-digital converter and intelligent controller for use in a DAQ
           system processing PMT signals from very high energy astrophysics
           experiments
    • Abstract: Publication date: Available online 24 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): N.I. Moseiko, A.I. Klimov, V.G. Sinitsyna, V.Y. Sinitsyna, K.A. Balygin, S.S. Borisov, A.M. Kirichenko, R.M. Mirzafatikhov, I.E. Ostashev Modern instrumentation for very high energy gamma-ray astronomy and astrophysics requires efficient and precise digitisation of PMT signals from Cherenkov light generated by incoming cosmic ray particles over the energy range from hundreds of GeV up to several hundred TeV. This dynamic range of more than 1000 is coupled with a requirement for very low noise operation. We have developed modern multi-channel analog-to-digital converters (model BPA-8) together with a data acquisition system managed with an intelligent crate-controller (model K-167) which controls the measurement modules. The electronics described in this paper is accepted to be used to record PMT signals with high precision and efficiency, allowing reliable extraction and precise analysis of Cherenkov signals from high energy gamma-rays emitted by astrophysical objects.
       
  • A flat-field soft X-ray spectrometer for X-ray absorption spectroscopy
           measurement of warm dense matter
    • Abstract: Publication date: Available online 23 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Gyeongbo Kang, Minju Kim, Leejin Bae, Seong Hyeok Yang, Min Sang Cho, Chuin Hong Yap, Jae Hyung Jung, Seung Woo Kang, Il Woo Choi, Chang Hee Nam, Byoung Ick Cho A flat-field soft X-ray spectrograph operating in the spectral range of 250–1240 eV was designed and built for warm dense matter and high-energy density plasma physics. It employs a grazing incidence toroidal mirror as a focusing optic, an aberration-corrected variable line spacing concave grating with 2400 lines/mm as a dispersive element, and a charge coupled device as an X-ray detector. The dispersion and energy resolution are calibrated with a high-power laser-produced plasma and X-ray free electron laser sources. A resolving power over 370 was achieved over the entire spectral range. A super broadband spectrum in the range of 250–1000 eV was measured from the laser-produced bismuth plasma. The signal-to-noise of 130 was obtained with an average of 10 pulses. These results demonstrate the capability of the spectrograph for single laser shot based experiments for warm dense matter and high energy density plasma research.
       
  • Optimization of X-ray image acquisition and reconstruction for a C-arm
           CBCT system with a flat-panel detector
    • Abstract: Publication date: Available online 22 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Bo Kyung Cha, Seongchae Jeon, Chang-Woo Seo, Jongduck Back, Shinkook Choi, Changwoo Lee, Miseob Ahn A modern cone-beam computed tomography (CBCT) system with a C-arm gantry incorporating a large-area flat-panel detector is an important imaging tool widely used for diagnosis and image-guidance in spine surgery, orthopedic and interventional suite, and image-guided radiation therapy. In this study, the experimental prototype CBCT imaging platform consists of a benchtop system that is integrated with a cone-beam X-ray tube, a collimator, an anti-scatter grid, and a large-area TFT-based flat-panel detector. The different projection images in the C-arm CT system were usually acquired at short scanning angles with a constant interval for various exposure conditions. The performance of CT imaging quality was performed using the Feldkamp, Davis and Kress(FDK) reconstruction algorithm through acquired two-dimensional projection images at different scanning angles and projection numbers. Quantitative analysis of the image quality was performed by using the cone-beam CT phantom for spatial resolution, low-contrast resolution, noise, and two different phantoms, such as the head and pelvis.
       
  • Information driven safeguards approach for remote monitoring system of dry
           cask storage
    • Abstract: Publication date: Available online 22 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Athena Sagadevan, Sunil Chirayath The lack of an operational deep geological repository in the U.S. has left the nuclear power plant operators with the option of storing the more than five years water cooled spent nuclear fuel (SNF) assemblies in dry casks as an interim solution. A single dry cask that typically stores 32 pressurized water reactor (PWR) SNF assemblies can contain up to 20 significant quantities (SQ) of plutonium. A disadvantage of using dry casks from a nuclear safeguards perspective is that there is currently no effective way of re-verifying its contents after it has been sealed. Current safeguards measures rely on containment and surveillance (C&S) techniques primarily by using seals and optical surveillance systems. Nonetheless, if the seal is broken, there is no method to verify the contents of a cask without opening it. This endeavor of opening the cask would expose the personnel involved to high levels of radiation in addition to being expensive and undesirable. Hence, a remote monitoring system (RMS) is designed, analyzed and the results presented here. The RMS combines nondestructive analysis (NDA) and C&S to collect and transmit data continuously to the authorities so that the international atomic energy agency (IAEA) can fulfil its requirement of maintaining continuity of knowledge (CoK) and thus verifying the contents of the dry casks without having to ever open them. The study performed uses radiation transport simulations and analysis of the results, specifically neutron transport simulations for the radiation source term present inside the SNF assemblies. Simulations for this study includes removal of a selected number of SNF assemblies from a multipurpose canister (MPC) and substitution with dummy assemblies. Eight SNF assembly diversion scenarios are analyzed through neutron radiation transport simulations. A neutron transport simulation with all the 32 SNF assemblies present inside the MPC and the corresponding neutron signal on the top of the MPC is used as the reference to compare to the reduction in neutron signal for each of the diversion scenarios. A false alarm probability, (α) of 5% is set for the reference case to determine the threshold for detecting the SNF assembly diversion. Simulation results and the analysis showed that the non-detection probability (β) for each SNF assembly diversion case is less than 20% and thus serve as a proof of concept that even diversion of a single SNF assembly is detectable. In addition, 32 252Cf point sources with source strengths mimicking that of SNF assemblies were simulated in a similar configuration within the MPC, which also provided similar results. This study is a proof of concept in order for experiments to be conducted to validate the simulation results. All the simulations are performed using the multi-purpose Monte Carlo Radiation Transport Code, MCNP 6.
       
  • Future upgrades of the LHCb RICH
    • Abstract: Publication date: Available online 21 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Sajan Easo, On behalf of LHCb RICH collaboration The two RICH detectors in LHCb have successfully collected data corresponding to 7 fb−1 of integrated luminosity since 2010 and have been essential for most of the physics programme of LHCb. Preparations are underway to upgrade them for the run starting in 2021. The long term physics goals of LHCb call for a further major upgrade of the detector system to collect data corresponding to 50 fb−1 of integrated luminosity by 2029 and 300 fb−1 thereafter.Feasibility studies are underway for measuring the time of arrival of the photons on the RICH detector plane in addition to their spatial coordinates. Simulation studies show how the RICH hit time information can be used to improve the particle identification performance. Silicon photomultipliers help to improve the RICH angular resolution without reducing the photon yield. Options to use novel radiators for extending the momentum coverage are being considered.
       
  • In-situ characterization of the Hamamatsu R5912-HQE photomultiplier tubes
           used in the DEAP-3600 experiment
    • Abstract: Publication date: Available online 20 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): P.-A. Amaudruz, M. Batygov, B. Beltran, C.E. Bina, D. Bishop, J. Bonatt, G. Boorman, M.G. Boulay, B. Broerman, T. Bromwich, J.F. Bueno, A. Butcher, B. Cai, S. Chan, M. Chen, R. Chouinard, S. Churchwell, B.T. Cleveland, D. Cranshaw, K. Dering The Hamamatsu R5912-HQE photomultiplier-tube (PMT) is a novel high-quantum efficiency PMT. It is currently used in the DEAP-3600 dark matter detector and is of significant interest for future dark matter and neutrino experiments where high signal yields are needed.We report on the methods developed for in-situ characterization and monitoring of DEAP’s 255 R5912-HQE PMTs. This includes a detailed discussion of typical measured single-photoelectron charge distributions, correlated noise (afterpulsing), dark noise, double, and late pulsing characteristics. The characterization is performed during the detector commissioning phase using laser light injected through a light diffusing sphere and during normal detector operation using LED light injected through optical fibres.
       
  • End-user experience with the SCoTSS Compton imager and directional survey
           spectrometer
    • Abstract: Publication date: Available online 19 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Laurel E. Sinclair, Andrew McCann, Patrick R.B. Saull, Nathan Murtha, Rodger L. Mantifel, Christian V.O. Ouellet, Pierre-Luc Drouin, Audrey M.L. Macleod, Brian Le Gros, Ian Summerell, Jens H. Hovgaard, Stephen Monkhouse, Flaviu Stanescu, Guy Jonkmans The Silicon photomultiplier-based Compton Telescope for Safety and Security (SCoTSS) has been developed incorporating end-user requirements into the design process. The end-user group includes those responsible for mobile survey in the event of a radiological or nuclear accident, those responsible for radiation survey support to security operations at major events and at Canadian borders, as well as some of those responsible for Canadian defense applications. The SCoTSS development program has reached a technology readiness level of eight, and we are proceeding with field trials of the instrument in high-fidelity operational environments. Prospective end users have been involved in trial set up and execution, assuring applicability in their mission spaces. SCoTSS has been subject to trials involving hidden sources, heavily shielded sources, imager moving with respect to source, and complicated man-made surroundings. Our operators value high sensitivity for anomaly geolocation and mapping. End users also require an instrument which is capable of direction reconstruction in motion, as well as rapid imaging of a field of view. We have developed a “time to image” measure which allows for quantitative comparison of imagers of fundamentally different technology, where one design may have an advantage in terms of energy resolution and compactness and another design may have an advantage in terms of efficiency and cost effectiveness. We present here the performance of the SCoTSS imager in rapid direction finding. As well, we compare the time to image quantity for the SCoTSS imager and the H3D Polaris-H Quad imager where the data were taken under equivalent conditions. This quantitative measure of imaging performance can allow operators to make an informed choice of the design that meets their needs taking into consideration also weight and size as well as budgetary constraints.
       
  • Cherenkov water detector NEVOD and its further development
    • Abstract: Publication date: Available online 19 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): A.A. Petrukhin NEVOD is the first and the only in the world Cherenkov water detector (CWD) for investigations of all cosmic ray components on the Earth’s surface. Conception of quasispherical modules for detection of Cherenkov light in water from any direction with an equal efficiency is analyzed. Additional detectors for CWD and results of various investigations are discussed. The future development of the CWD NEVOD as a test facility for calibration of new optical modules for very large volume neutrino telescopes is considered.
       
  • Particle-level model for radar based detection of high-energy neutrino
           cascades
    • Abstract: Publication date: Available online 19 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): S. Prohira, D. Besson We present a particle-level model for calculating the radio scatter of incident RF radiation from the plasma formed in the wake of a particle shower. We incorporate this model into a software module (“RadioScatter”), which calculates the collective scattered signal using the individual particle equations of motion, accounting for plasma effects, transmitter and receiver geometries, refraction at boundaries, and antenna gain patterns. We find appreciable collective scattering amplitudes with coherent phase for a range of geometries, with high geometric and volumetric acceptance. Details of the calculation are discussed, as well as the implementation of RadioScatter into GEANT4. A laboratory test of our model, currently scheduled at SLAC in 2018, with the goal of measuring the time-dependent characteristics of the reflecting plasma, is also described. Prospects for a future in-ice, high-energy neutrino detector, along with comparison to current detection strategies, are presented.
       
  • Optimization of electromagnetic and hadronic extensive air showers
           identification using muon detectors of TAIGA experiment
    • Abstract: Publication date: Available online 19 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): I. Astapov, P. Bezyazeekov, V. Boreyko, A. Borodin, M. Brueckner, N. Budnev, A. Chiavassa, A. Dyachok, O. Fedorov, A. Gafarov, A. Garmash, N. Gorbunov, V. Grebenyuk, O. Gress, T. Gress, O. Grishin, A. Grinyuk, D. Horns, A. Ivanova, N. Kalmykov The TAIGA experiment at Tunka valley near Baikal is planning to extend with new TAIGA-Muon scintillation detector stations. It is mainly for advanced study of astroparticles. The experimental setup of TAIGA-Muon is modeled by using GEANT4 software package. Monte Carlo simulation of experiment is done with software packages, CORSIKA and GEANT4. Extensive air showers of primary particles with energy range 100-3000 TeV are created with CORSIKA. The trigger efficiency is calculated and optimized the thickness of absorber to 2 m. The suppression factor of electromagnetic showers from hadronic showers is studied and this study leads us to find the optimum depth of soil, lowest energy range. Data on the detection efficiency for primary gamma-quanta and proton events are presented as well as suppression factor.
       
  • A transportable neutron spin filter
    • Abstract: Publication date: Available online 18 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Y. Quan, B. van den Brandt, J. Kohlbrecher, W.Th. Wenckebach, P. Hautle We report a transportable neutron spin filter based on the strong spin dependence of neutron proton scattering. The necessary high proton polarization is created by dynamic nuclear polarization (DNP) that uses short-lived optically excited triplet states instead of stable radicals, which eliminates the main path of nuclear spin lattice relaxation. The polarization can be preserved for many days under moderate experimental conditions and allows to realize a transportable spin filter which is conveniently polarized in the laboratory and then operated on a neutron beam line with practically frozen polarization maintained with a minimum of equipment. Using triplet DNP bulk proton spins in a pentacene doped single crystal of naphthalene have been polarized to a record value of 80% at a field of 0.36 T using a simple helium flow cryostat for cooling. This highly polarized sample can be transported in the compact cryostat without loss of polarization to a neutron beam line where it serves as a spin filter for polarization analysis in a neutron scattering experiment. Relaxation times of T1∼800 h are achieved at a field of 20 mT and the polarization can be reversed by adiabatic fast passage with an efficiency of above 99%.
       
  • γ +radiography+for+the+characterization+of+low-mass,+solid-phase+media&rft.title=Nuclear+Instruments+and+Methods+in+Physics+Research+Section+A:+Accelerators,+Spectrometers,+Detectors+and+Associated+Equipment&rft.issn=0168-9002&rft.date=&rft.volume=">The potential of real-time, fast neutron and γ radiography for the
           characterization of low-mass, solid-phase media
    • Abstract: Publication date: Available online 18 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): M. Licata, M.J. Joyce, I. Tsitsimpelis, D. Clark, B.A. Shippen Most techniques that are used for transmission imaging with ionising radiation use X-rays, which have the advantage of providing quick, high-resolution images with a relatively small dose of radiation. However, they also have the disadvantage that their penetrating power can be limited in some forms of matter. This can make the discrimination of materials with a low atomic number particularly challenging. Of specific interest in this regard is the need to screen a diversity of manmade items that are heterogeneous and with the tendency to have many interfaces between components that can comprise a diversity of low-mass elements and compounds. These items usually have a compact geometry and a high density of components, which can make them less easy to be imaged quickly and effectively with X-rays. This limit of current screening technology necessitates further stages of examination reducing the ease with which this is done for manufacturing and quality assurance applications. The results presented in this paper demonstrate that, either via fast-neutron radiography or tomography, the potential exists to discern a variety of low-A compounds from one another. Via Monte Carlo simulations, it will be shown that fast-neutron radiography undertaken with a portable, isotopic radiation source (californium-252), absorption and scattering by the doped polymeric materials yields a degree of distinction from other substances. Considering these results, the state-of-the-art of the technique leading to the realization of a combined, real-time fast-neutron and γ-ray radiography system will also be presented, as well as the first experimental results.
       
  • Radiation tests of Hamamatsu multi-pixel photon counters
    • Abstract: Publication date: Available online 18 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): G. Blazey, J. Colston, A. Dyshkant, K. Francis, J. Kalnins, S.A. Uzunyan, V. Zutshi, S. Hansen, P. Rubinov, E.C. Dukes, Y. Oksuzian, M. Pankuch Results of radiation tests of Hamamatsu 2.0 × 2.0 mm2 through-silicon-via (S13360-2050VE) multi-pixel photon counters, or MPPCs, are presented Hamamatsu (0000). Distinct sets of eight MPPCs were exposed to four different 1 MeV neutron equivalent doses of 200 MeV protons. Measurements of the breakdown voltage, gain and noise rates at different bias overvoltages, photoelectron thresholds, and LED illumination levels were taken before and after irradiation. Comparisons are made to the 1.3 × 1.3 mm2 S13360-1350PE MPPCs which utilize a non-TSV (through-silicon-via) architecture. These studies were undertaken in the context of MPPC requirements for the Cosmic Ray Veto detector of the Mu2e experiment at the Fermi National Accelerator Laboratory.
       
  • LuAG ceramic scintillators for future HEP experiments
    • Abstract: Publication date: Available online 18 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Chen Hu, Jiang Li, Fan Yang, Benxue Jiang, Liyuan Zhang, Ren-Yuan Zhu Because of its bright and fast scintillation cerium-doped Lu3Al5O12 (LuAG:Ce) crystals have attracted an interest in the high energy physics community. Compared to inorganic crystals, fabrication of ceramic scintillators features with a lower temperature and a more effective use of raw materials, thus promising cost-effective inorganic scintillators. Our investigations revealed excellent radiation hardness of LuAG:Ce ceramics in both transmittance and light output against an ionization dose up to 200 Mrad and a proton fluence up to 3×1014 p/cm2. We also investigated light output and decay kinetics for LuAG:Ce ceramics with different Ce doping levels and various co-dopings. The results show increased light output and slow scintillation component when the Ce doping level increases. Ca2+ co-doping is found effective in suppressing slow scintillation component in LuAG:Ce ceramics. We also discuss the status of LuAG ceramic scintillators and future development plan.
       
  • Investigation of Compton scattering for gamma beam intensity measurements
           and perspectives at ELI-NP
    • Abstract: Publication date: Available online 18 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): G.V. Turturica, C. Matei, A. Pappalardo, D.L. Balabanski, S. Chesnevskaya, V. Iancu, C.A. Ur, H.J. Karwowski, K.A. Chipps, M.T. Febbraro, S.D. Pain, D. Walter, C.Aa. Diget, J. Frost-Schenk, M. Munch, G.L. Guardo, M. La Cognata, R.G. Pizzone, G.G. Rapisarda, K.Y. Chae Compton γ-ray sources have been in operation for over 30 years with new facilities being under construction or proposed. The gamma beam system under implementation at the Extreme Light Infrastructure – Nuclear Physics facility in Romania will deliver brilliant γ-ray beams with energies up to 19.5 MeV. Several instruments for measuring the parameters of the γ-ray beam are under development at ELI-NP. One of these instruments based on a High Purity Germanium detector is routinely used for beam energy measurements at other facilities. Here we investigate the use of a High Purity Germanium detector to continuously monitor the intensity of the ELI-NP gamma beam by measuring the inelastic scattering of photons. This method relies on both experimental and simulated data and it has been successfully tested during a recent experiment at the High Intensity γ-ray Source facility.
       
  • A neural network approach for identification of gamma-ray spectrum
           obtained from silicon photomultipliers
    • Abstract: Publication date: Available online 18 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Seungho Jhung, Seop Hur, Gyuseong Cho, Inyong Kwon This paper presents a neural network approach for the identification of gamma emitting radionuclides measured by Silicon Photomultipliers (SiPMs). SiPMs have wide-ranging applications in the field of radiation monitoring and medical imaging due to their high quantum efficiency, high gain, and compactness. For better accuracy on the measured information, however, we should consider the disadvantages: dark count rate, optical crosstalk, and temperature sensitivity. Regarding temperature dependencies, conventional approaches are mainly focused on compensating gain variances against temperature by adding circuits or calibrating signals. In contrast with previous works, we propose a new approach exploiting two-layer fully connected neural network with a SiPM. The neural network is composed of rectified linear unit (ReLU) layers and a softmax layer. A Saint-Gobain Lutetium-yttrium oxyorthosilicate (LYSO) and a SensL MicroFJ SiPM combined with a charge sensitive amplifier (CSA) circuit were used in the data acquisition to detect 137Cs and 152Eu. The decreasing logistic regression cost function shows that the proposed neural network converges to a global minimum, verifying the possibility of distinguishing Cesium from Europium in the mixed radioactive environment.
       
  • Fabrication and experimental evaluation of microstructured 6Li silicate
           fiber arrays for high spatial resolution neutron imaging
    • Abstract: Publication date: Available online 17 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Michael E. Moore, Joris Lousteau, Pavel Trtik, Hassina Z. Bilheux, Diego Pugliese, Daniel Milanese, Angela T. Simone, Gilberto Brambilla, Jason P. Hayward This work presents the fabrication and experimental evaluation of instrumentation designed to enable higher spatial resolution neutron radiography for those performing research at neutron scattering facilities. Herein, we describe a proof-of-concept array of microstructured silicate fibers with  6Li doped cores that shows progress towards a design for μm resolution neutron radiography. The multicore fiber was fabricated by drawing stacked unit elements of Guardian Glass (Nucsafe Inc., Oak Ridge, TN, USA), a  6Li scintillating core glass, and a silicate cladding glass. These structured fibers function as an array of sub-10-μm waveguides for scintillation light. Measurements have shown a significantly increased integrated charge distribution in response to neutrons, and the spatial resolution of the radiographs is described by edge response and line spread functions of 48±4μm and 59±8μm, respectively.
       
  • Calibration method of center of rotation under the displaced detector
           scanning for industrial CT
    • Abstract: Publication date: Available online 17 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Qiang Lin, Min Yang, Fanyong Meng, Liang Sun, Bin Tang For computed tomography, projection center of rotation (COR) is a significant reconstruction parameter which needs to be precisely measured before an image reconstruction. Otherwise, serious flame-shaped artifacts will arise in the CT images. In particular, when a displaced detector scanning mode is used for the inspection of a large object, the line connecting the X-ray focus and the COR is not perpendicular to the detector, making the calibration of the COR more difficult In this paper, a new calibration method of the COR based on the symmetrical property of a sinogram is proposed. According to this method, the possible COR is enumerated among a range and the original sinogram is transformed onto a virtual detector. Then all the variances between the sum of the projection data on the left half side of the virtual detector and that on the right half side of the virtual detector are calculated. Finally, the accurate COR is determined by seeking out the minimum value of the variances. The proposed method doesn’t need any dedicated phantom to complete the calibration, but rather directly makes use of the sinogram of the scanned sample to search the COR. Because all the projection data collected by a detector unit is summed up to perform the calibration, the algorithm is not sensitive to random noise, which has been proved by the simulated data with high-level noise and the experimental data.
       
  • The upgrade of the LHCb RICH detectors
    • Abstract: Publication date: Available online 17 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Massimiliano Fiorini The LHCb Ring-Imaging Cherenkov (RICH) detector system has been operated with very high availability in the LHCb experiment since 2009, performing charged hadron identification in a wide momentum range with high efficiency and providing crucial information for most physics analyses. The LHCb experiment will undergo a major upgrade during the second LHC long shutdown (2019-2020), improving many of its detector systems in order to sustain the current particle identification performance in conditions of a five-fold increase of the instantaneous luminosity (up to 2 × 1033 cm−2 s−1) compared to the current running conditions. In particular, a substantial change in the LHCb trigger and read-out schemes will be implemented to allow 40 MHz continuous data taking. The RICH detectors will be upgraded by installing new single-photon detectors (multi-anode photomultiplier tubes in place of hybrid photo-detectors) read out by 40 MHz capable electronics, and by modifying the upstream RICH optics and mechanics. An overview of the RICH upgrade program is presented, including a summary of the expected performances and the result of the latest tests of the complete photo-electronics chain in the laboratory and test-beams.
       
  • Design and desktop experiment of LLRF system for CYCIAE-230
           superconducting cyclotron
    • Abstract: Publication date: Available online 17 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Z.G. Yin, P.F. Gong, J.Y. Wei, X.L. Fu The CYCIAE-230 cyclotron is a proton beam accelerator dedicated to cancer therapy. The low-level radiofrequency (LLRF) system of CYCIAE-230 cyclotron is designed based on the previous LLRF systems which have been successfully commissioned for CYCIAE-100 and CYCIAE-14 cyclotrons. This design includes four feedback control loops, namely, tuning loop, amplitude loop, phase loop, and balance loop. The LLRF system for CYCIAE-230 cyclotron have the same amplitude, phase, and tuning loops as the previous designs. Meanwhile, the balance loop makes the LLRF system stand out. It’s enabled after the amplitude loop is closed and controls the homogeneity of the accelerating fields of the four cavities. From the bird view of the control system of the cyclotron, the LLRF system is an embedded control unit which communicates with the program logical controller with Profibus-DP (Distributed Peripherals). In this paper, the desktop experiment has been performed with a small-scale copper cavity with low power. This small-scale cavity has an unloaded quality factor (Q0) of around 7800 and has push–pull and push–push resonate modes, which are the characteristic parameters of the cavities of CYCIAE-230 cyclotron. The design and performance of the LLRF system were discussed based on the desktop experiment results in this paper.
       
  • Prototype time-of-flight PET utilizing capacitive multiplexing readout
           method
    • Abstract: Publication date: Available online 17 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Hyeok-jun Choe, Yong Choi, Dong Jin Kwak, Junyung Lee Positron emission tomography (PET) is an imaging technique that provides the spatial distribution of radiopharmaceuticals labeled with positron emitting radioisotopes by detecting the gamma rays produced from positron-electron annihilation. Recently, a time-of-flight (TOF) PET has drawn an increasing attention because it is capable of reducing the scan time or injected dose with improved the signal-to-noise ratio (SNR) in reconstructed PET images by precisely localizing the emission point along the line-of-response using TOF information.This study presents a multiplexing method that can effectively reduce the number of readout channels of a silicon photomultiplier (SiPM) based TOF PET while achieving excellent timing resolution. A capacitive multiplexing method was employed that could improve the degradation of the timing performance occurring in a conventional resistive multiplexing method. In addition, a high-speed signal processing method is also presented for the TOF PET. A TOF PET prototype was developed to demonstrate the imaging capability of the TOF PET system.A flood histogram of a PET detector module, composed of an 8×8 array of 3.01×3.01×20.00 mm3 lutetium fine silicate (LFS) scintillators and an 8×8 array of 3.16×3.16 mm2 SiPMs, was acquired using the proposed method. All 64 scintillators were successfully resolved in the flood histogram. The average energy resolution and coincidence resolving time (CRT) were 14.2 ± 1.1% and 431 ± 41 ps full width at half maximum (FWHM), respectively. A tomographic image of the hot-rod phantom was successfully acquired using the TOF PET prototype, and rods with a size of 2.4 mm in diameter were clearly resolved in the reconstructed image.
       
  • Front-end electronics of the Belle II aerogel ring imaging detector
    • Abstract: Publication date: Available online 17 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): R. Pestotnik, I. Adachi, L. Burmistrov, F. Le Diberder, R. Dolenec, K. Hataya, S. Kakimoto, H. Kakuno, H. Kawai, T. Kawasaki, H. Kindo, T. Konno, S. Korpar, P. Križan, T. Kumita, Y. Lai, M. Machida, M. Mrvar, S. Nishida, K. Noguchi A proximity focusing RICH detector with an aerogel radiator is used for charged particle identification in the forward end-cap of the Belle II spectrometer. The detector, consisting of a 4 cm aerogel radiator, a 16 cm expansion volume and a photon detector with 420 Hybrid Avalanche Photo Detectors, is mounted in a very confined space between Central Drift Chamber and Electromagnetic Calorimeter, allowing only 5 cm of space for the readout electronics. In our solution, low power front-end read-out boards are mounted at the back side of each of the HAPD photosensors. These boards have each been tested individually before their installation onto the photosensors and into the spectrometer. Most important design issues and first experiences with the aforementioned front-end read-out boards are presented in this contribution.
       
  • Development of a high frame rate neutron imaging method for two-phase
           flows
    • Abstract: Publication date: Available online 17 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): C. Lani, R. Zboray A high frame rate neutron imaging system has been developed at the Pennsylvania State University utilizing the Breazeale TRIGA reactor in the Radiation Science and Engineering Center. The imaging setup uses the pulsing capabilities of the TRIGA reactor to obtain neutron images at frame rates up to 4000 frames per second. The system was used to image an aluminum bubbler which forced compressed air through water creating a two-phase flow mixture. This paper describes the equipment used for the setup and its performance with respect to time and space resolution and analyzes various potential biasing effects for quantitative results such as statistical error and low count bias.
       
  • Events reconstruction at 30 MHz for the LHCb upgrade
    • Abstract: Publication date: Available online 16 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): T. Szumlak The Large Hadron Collider (LHC) Run 2 data taking period is coming to its end this year (2018). With the upcoming Long Shutdown 2 that will last till the end of 2020 we enter the upgrade era for the LHC based experiments. The LHCb experiment is going for a major upgrade (called LHCb Upgrade I) that practically affects all hardware components of the experimental setup as well as the DAQ and trigger. The LHCb event reconstruction procedure needs to face the challenge of fulfilling extremely tight time constraints imposed by a fully software trigger system running at the frequency of 30 MHz what corresponds to the inelastic event rate. At the same time this real time system must ensure the high level of physics performance needed by the LHCb scientific programme. This challenge requires rethinking and optimising the logic of the event reconstruction algorithms, exploiting to the best the detectors properties and adopting out-of-the-box innovative ideas.
       
  • Protection of the in-vacuum-operating straw chambers from vacuum
           penetration
    • Abstract: Publication date: Available online 15 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): L. Glonti, G. Glonti, V. Kekelidze, S. Movchan, N. Ridinger, Yu. Potrebenikov, V. Samsonov, V. Chepurnov In the past years, drift chambers with straws operating in high vacuum (∼ 10−5 mb) has become to be used in experimental studies of rare decays. Any drift tube of the operating chamber may suffer a mechanical or electrical damage and a subsequent leak. The complete failure of the tube is not excluded either. To protect the chambers against the above damage, we have developed a simple protection system based on uniquely designed devices. If air-tightness is broken and gas starts leaking from the tube into the vacuum, they automatically cut off the gas flow on both ends of the damaged tube and disconnect it from the gas supply.
       
  • Resonant feedback for axion and hidden sector dark matter searches
    • Abstract: Publication date: Available online 15 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Edward J. Daw Resonant feedback circuits are proposed as an alternative to normal modes of conducting wall cavities or lumped circuits in searches for hidden sector particles. The proposed method offers several potential advantages over the most sensitive axion searches to date, including coverage of a wider range of axion masses, the ability to probe many axion masses simultaneously, and the elimination of experimentally troublesome mechanical tuning rod mechanisms. After an outline of the proposed method, we present a noise budget for a straw-man experiment configuration. We show that the proposed experiment has the potential to probe the axion mass range 2–40 μeV with 38 days of integration time. Other existing and proposed resonant searches for hidden sector particles may also benefit from this approach to detection.
       
  • Energy response of GECAM gamma-ray detector based on LaBr3:Ce
           and SiPM array
    • Abstract: Publication date: Available online 13 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Dali Zhang, Xinqiao Li, Shaolin Xiong, Yanguo Li, Xilei Sun, Zhenghua An, Yanbing Xu, Yue Zhu, Wenxi Peng, Huanyu Wang, Fan Zhang The Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) , composed of two small satellites, is a new mission to monitor the Gamma-Ray Bursts (GRBs) coincident with Gravitational Wave (GW) events with a FOV of 100% all-sky. Each GECAM satellite detects and localizes GRBs using 25 compact and novel Gamma-Ray Detectors (GRDs) in 6 keV–5 MeV. Each GRD module is comprised of LaBr3:Ce scintillator, SiPM array and preamplifier. A large dynamic range of GRD is achieved by the high gain and low gain channels of the preamplifier. The energy response of GRD prototype was evaluated using radioactive sources in the range of 5.9–1332.5 keV. A energy resolution of 5.3% at 662 keV was determined from the 137Cs pulse height spectra, which meets the GECAM requirement (
       
  • Timing performance of organic scintillators coupled to silicon
           photomultipliers
    • Abstract: Publication date: Available online 13 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): W.M. Steinberger, M.L. Ruch, A. Di-Fulvio, S.D. Clarke, S.A. Pozzi This work compares the time resolution obtained from coincidence measurements using combinations of four types of silicon photomultipliers (SiPMs), five types of organic scintillators, and two timing algorithms. Organic scintillators in combination with SiPMs have shown to have equivalent or better time resolution and pulse shape discrimination (PSD) capability than with photo-multiplier tubes (PMTs). In addition, SiPMs are more compact and require low operating voltage. These factors have made them suitable for the development of compact neutron scatter cameras (NSCs) and potentially low-cost positron emission tomography (PET) systems. The following measurements analyze combinations of organic scintillators and SiPMs that could be used for these applications. Measurements and analyses assessed the time resolution of standard-output and fast-output pulses of the various scintillator and SiPM combinations. The coincidence measurements were performed using a Na-22 source to characterize time resolution where all coincident events above about a 40 keVee threshold were analyzed. Uncertainties were determined by applying bootstrapping to the acquired data sets. The full width at half maximum (FWHM) of the time difference distribution for each combination is reported as the time resolution of the system. For standard-output pulses, we found that using a digital implementation of analogue constant fraction discrimination (DIACFD) improved timing resolution greater than a single standard deviation for six of the fourteen tested combinations compared to using digital constant fraction discrimination (DCFD). Conversely, for fast-output pulses, DCFD with a moving average filter produced the best timing resolution. Among the tested non-PSD capable organic scintillators, EJ-228 coupled to a MicroFJ-SMA-60035 SensL SiPM yielded the best time resolution of 303 ± 4 ps for standard-output pulses and 227 ± 4 ps for fast-output pulses. The best time resolution found for PSD capable organic scintillators was obtained using Inrad Optics stilbene coupled to a MicroFJ-SMA-60035 SensL SiPM which yielded a time resolution of 428 ± 6 ps for standard-output pulses and 293 ± 4 ps for fast-output pulses.
       
  • A simple method for a very short X-ray pulse production and attosecond
           diagnostic at LCLS
    • Abstract: Publication date: Available online 12 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Alexander Novokhatski, Dorian Bohler, Axel Brachmann, William Colocho, Franz-Josef Decker, Alan S. Fisher, Marc Guetg, Richard Iverson, Patrick Krejcik, Jacek Krzywinski, Alberto Lutman, Timothy Maxwell, Michael Sullivan We discuss how by using the wake fields generating in a corrugating plate we may increase the resolution of a transverse diagnostic cavity while producing an extremely short X-ray pulse at LCLS.
       
  • Imaging of plutonium particles using a CCD-camera-based alpha-particle
           imaging system
    • Abstract: Publication date: Available online 11 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Yuki Morishita Measuring individual activities of Plutonium dioxide (PuO2) particles is extremely important for the internal exposure of a worker to these particles. For this purpose, a film-based autoradiographic camera, Imaging Plates, and a SiPM-based alpha particle imaging detector have been used in a site of nuclear facilities. However, there is a room for improvement regarding a spatial resolution or a quantification of activity. Recently, an alpha imaging system using a cooled CCD camera has been developed and used for detecting Pu contamination in a glove box. In this study, actual PuO2 particles were measured using the CCD-camera-based alpha-particle imaging system, and the system’s effectiveness was proven by comparing to conventional systems. An electron multiplying (EM) CCD Camera (ImagEM X2 C9100-23B, Hamamatsu, Japan) was used for alpha particle imaging in this study. A Pu sample was placed on top of the ZnS(Ag) scintillator, and produced scintillation light was captured using the CCD camera. The number of alpha particles on a 2-dimensional distribution image was measured to convert into activity. The frame rate for obtaining the image was set to 33.3 frames/s (at 30 ms intervals). This study showed that the CCD camera-based alpha-particle imaging system has some advantages compared to the conventional alpha particle imaging systems; 1) High spatial resolution, 2) Counting capability of individual alpha particles, 3) Real-time imaging.
       
  • α -particle+beams&rft.title=Nuclear+Instruments+and+Methods+in+Physics+Research+Section+A:+Accelerators,+Spectrometers,+Detectors+and+Associated+Equipment&rft.issn=0168-9002&rft.date=&rft.volume=">Blister resistant targets for nuclear reaction experiments with
           α -particle beams
    • Abstract: Publication date: Available online 10 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Sean Hunt, Camden Hunt, Christian Iliadis, Michael Falvo Solid targets for nuclear measurements that use α-particle beams commonly experience a form of degradation known as blistering. The effect can prevent the use of solid targets for high intensity α-particle experiments, often necessitating complex gas target systems. To combat this problem, three different blister resistant target backings were designed for use in direct reaction measurements with high intensity α-particle beams. The blister resistant target designs utilize gas diffusive properties of fused silica, sintered metal, and porous evaporated metal. Each target was implanted with 22Ne ions and bombarded with α-particle beam to test blister resistance. Targets were characterized and monitored using the 22Ne(p,γ)23Na reaction to determine the degradation of implanted material, and compare them to typical implanted noble gas targets. We find that all targets studied exhibit resistance to blistering, with the porous evaporated metal targets displaying the least amount of target material degradation.
       
  • Study of energy and timing characteristics of 38.1mm × 38.1mm CeBr3
           scintillator detectors
    • Abstract: Publication date: Available online 10 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): G. Mishra, R.G. Thomas, Ajay Kumar, A. Mitra, S. De, S.V. Suryanarayana, B.K. Nayak We report the results of measurements and GEANT4 simulation for the performance of two 38.1mm × 38.1mm CeBr3 detectors. The linearity and energy resolution of both the detectors have been measured using low energy gamma sources in the range from 121.8 keV to 4.44 MeV. Maintaining the energy linearity condition, the best time resolution value of 423 ± 14 ps was measured for 1173-1332 keV photon pair from a 60Co source. A GEANT4 simulation was performed to reproduce the measured experimental spectrum and to estimate the absolute photopeak efficiencies at several energies up to 4.44 MeV.
       
  • A neutron beam monitor based on silicon carbide semiconductor coated with
           6LiF converter
    • Abstract: Publication date: Available online 10 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Yong Jiang, Jian Wu, Zheng Li, Xiaoqiang Fan, Jiarong Lei A neutron beam monitor was developed for the time-of-flight neutron reflectometer (NR) instrument at the China Mianyang Research Reactor (CMRR). The SiC neutron monitor employs a wide-bandgap silicon carbide (SiC) semiconductor detector coated with a 6LiF neutron converter film evaporated on a thin ceramic sheet. Given the relatively large active area [(10 × 10) mm2] and sufficiently thick epitaxial layer (30μm), the monitor can discriminate the gamma background from the signals. Prior to assembling the monitor, the I–V characteristics and alpha responses of the SiC detector were measured. Next, the SiC detector and 6LiF neutron converter were installed in a small aluminum shielding box, and the neutron and gamma responses were measured with an Am–Li neutron source and a 137Cs plus 60Co gamma source, respectively. The fabricated SiC neutron monitor was mounted inside the slit of the NR instrument (after the focusing neutron guide), and the intensity of the transmitted neutron beam was measured. To measure the incident neutron flux, the distinct triton peaks from the 6Li (n, α) T reaction were counted as normalized data for the NR instrument. This paper describes the fabrication details of the SiC neutron monitor, and discusses the preliminary measurements.
       
  • Quantifying the determinants of leakage multiplication for large uranium
           objects using Monte Carlo simulations
    • Abstract: Publication date: Available online 10 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Matthew C. Tweardy, Seth McConchie, Jason P. Hayward Leakage multiplication is a physical characteristic of fissionable uranium objects that can be assayed using active interrogation measurements. Assay of large, highly-multiplying uranium objects using coincidence and multiplicity counting is susceptible to biases stemming from the simplistic assumptions of point kinetics-based analysis methods. This work uses Monte Carlo simulations and nonlinear curve fitting to quantify the sensitivity of leakage multiplication to enrichment, mass, and geometry for a range of bare uranium metal spheres, cylinders, and annular castings up to 7 kg under active interrogation. An understanding of how sensitive leakage multiplication is to changes in the underlying physical characteristics of uranium allows for potential corrections to assay results or evaluation of assay uncertainty based on prior or inferred knowledge of one or more of these physical characteristics.
       
  • Double photon emission coincidence imaging with GAGG-SiPM Compton camera
    • Abstract: Publication date: Available online 8 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Mizuki Uenomachi, Yuki Mizumachi, Yuri Yoshihara, Hiroyuki Takahashi, Kenji Shimazoe, Goro Yabu, Hiroki Yoneda, Shin Watanabe, Shin’ichiro Takeda, Tadashi Orita, Tadayuki Takahashi, Fumiki Moriyama, Hirotaka Sugawara Compton imaging is a promising gamma-ray imaging method based on the Compton scattering kinematics due to high Compton scattering probability for sub-MeV to MeV gamma-rays. A conventional Compton camera has a disadvantage of low signal-to-background ratio (SBR), which is caused by drawing of multiple Compton cones. A method to solve this fundamental problem is the double-photon emission computed tomography (DPECT), which uses the coincidence detection for cascade gamma-rays and significantly increases the SBR using intersections of two Compton cones. In this study, we demonstrated the DPECT method by using 134Cs radio isotope, which is one of important radioisotopes for the imaging of fuel debris, with two Ce:Gd3(Al,Ga)5O12 (GAGG) scintillator Compton cameras.
       
  • Bunch length scaling due to broadband impedance as a parameter for
           transverse feedback application
    • Abstract: Publication date: Available online 8 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Tae-Yeon Lee This paper investigates the possibility for suppression of the head-tail instability in an electron storage ring using a bunch-by-bunch transverse feedback system. General conditions are found whereby the Gaussian bunch profile may be modeled by a two-particle system which interacts with the vacuum chamber broadband impedance. We choose the kick factor received by a Gaussian bunch with the rms bunch length σt, from a broadband impedance with the resonance frequency ωr and quality factor Qr, as the relevant parameter and explain why the kick factor depends on ωrσt∕Qr. Finally, we demonstrate that a Gaussian bunch can be modeled by a two-particle system when the parameter ωrσt∕Qr is sufficiently small.
       
  • Neutrino astronomy and oscillation research in the Mediterranean: ANTARES
           and KM3NeT
    • Abstract: Publication date: Available online 7 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): Tommaso Chiarusi, On behalf of the ANTARES and KM3NeT Collaborations ANTARES, the underwater neutrino telescope in the Northern Hemisphere, has been continuously operating since 2007 in the Mediterranean Sea. The transparency of the water allows for a very good angular resolution in the reconstruction of interactions from neutrinos of all flavors. This results in unprecedented sensitivity for neutrino source searches in the Southern Sky at TeV energies, so that valuable constraints can be set on the origin of the cosmic neutrino flux discovered by the IceCube detector. Building on the successful experience of ANTARES the next generation KM3NeT neutrino telescope is now under construction in the Mediterranean Sea to significantly boost the sensitivity. Two detectors with the same technology but different granularity are under construction at two sites and will focus on high energy cosmic neutrinos (ARCA with Gton instrumented volume, offshore Capo Passero, Italy) and on atmospheric neutrinos at low energies down to a few GeV to address atmospheric neutrino oscillations (ORCA with Mtons instrumented volume, offshore Toulon, France). The basic KM3NeT detection element, the Digital Optical Module (DOM), houses 31 three-inch PMTs inside a 17 inch glass sphere. This multi-PMT concept allows for an accurate measurement of the light intensity (photon counting) and offers directional information with an almost isotropic field of view, at a reduced cost. This contribution will provide an overview on the newest results from ANTARES and an outlook towards the construction plan and exciting science potential of KM3NeT.
       
  • TM )+-+Pilot+production+and+development+status&rft.title=Nuclear+Instruments+and+Methods+in+Physics+Research+Section+A:+Accelerators,+Spectrometers,+Detectors+and+Associated+Equipment&rft.issn=0168-9002&rft.date=&rft.volume=">Large Area Picosecond Photodetector (LAPPD TM ) - Pilot production
           and development status
    • Abstract: Publication date: Available online 7 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): M.J. Minot, B.W. Adams, M. Aviles, J.L. Bond, T. Cremer, M.R. Foley, A. Lyashenko, M.A. Popecki, M.E. Stochaj, W.A. Worstell, M.J. Wetstein, J.W. Elam, A.U. Mane, O.H.W. Siegmund, C. Ertley, H.J. Frisch, A. Elagin, E. Angelico, E. Spieglan We report performance results achieved for fully functional sealed Large Area Picosecond Photodetectors (LAPPD™) in tests performed at Incom Inc., as well as independent test results reported by our early adopters. The LAPPD is a microchannel plate (MCP) based large area picosecond photodetector, capable of imaging with single-photon sensitivity at high spatial and temporal resolutions in a hermetic package. The LAPPD has an active area of 350 square centimeters in an all-glass hermetic package with a fused silica window and bottom plate and sidewalls made of borosilicate float glass. Signals are generated by a bi-alkali Na2KSb photocathode and amplified with a stacked chevron pair of MCPs produced by applying resistive and emissive atomic layer deposition coatings to glass capillary array (GCA) substrates. Signals are collected on RF stripline anodes applied to the bottom plates which exit the detector via pin-free hermetic seals under the side walls. LAPPD test and performance results for product produced and delivered to early adopter customers during the first half of 2018 are reviewed. These results include electron gains ≥ 7.5 × 106 @ 850/950 V (entry/exit MCP), low dark noise rates (22 Cts/s/cm2), single photoelectron (PE) timing resolution of 64 picoseconds RMS, and single photoelectron spatial resolution along and across strips of 2.8 mm and 1.3 mm RMS respectively. Many of these devices also had very high QE photocathodes that were uniform over the full 195 mm × 195 mm window active area (LAPPD #15 QE% @ 365 nm Max/Avg/Min = 25.8/22.3 ± 3/15.7). An update is also provided of developments that enable capacitive signal coupling from the detector to application specific pads or stripline readout patterns deployed on printed circuit boards positioned beneath the tile, outside of the vacuum package. We conclude with examples of how sensors offering picosecond timing, in diverse applications can bring transformative change to detector technology and applications in future experiments.
       
  • Computation of the impedance of a vacuum electron diode with emission
           current delay
    • Abstract: Publication date: Available online 7 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): I. Egorov, A. Poloskov, G. Remnev The paper analyses the computational reproducibility of impedance behavior of a vacuum electron diode with a significant delay of emission current. The adjustable model of the vacuum electron diode simulates typical periods of real impedance curves with some minor errors. The diode model tests simulate an energy release with an error less than 6% in comparison with a real diode, thus making the computation of accelerator regimes feasible.
       
  • Status of the TORCH time-of-flight project
    • Abstract: Publication date: Available online 7 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): N. Harnew, S. Bhasin, T. Blake, N.H. Brook, T. Conneely, D. Cussans, M. van Dijk, R. Forty, C. Frei, E.P.M. Gabriel, R. Gao, T.J. Gershon, T. Gys, T. Hadavizadeh, T.H. Hancock, M. Kreps, J. Milnes, D. Piedigrossi, J. Rademacker TORCH is a time-of-flight detector, designed to provide charged π∕K particle identification up to a momentum of 10 GeV/c for a 10 m flight path. To achieve this level of performance, a time resolution of 15 ps per incident particle is required. TORCH uses a plane of quartz of 1 cm thickness as a source of Cherenkov photons, which are then focussed onto square Micro-Channel Plate Photomultipliers (MCP-PMTs) of active area 53 × 53 mm2, segmented into 8 × 128 pixels equivalent. A small-scale TORCH demonstrator with a customised MCP-PMT and associated readout electronics has been successfully operated in a 5 GeV/c mixed pion/proton beam at the CERN PS facility. Preliminary results indicate that a single-photon resolution better than 100 ps can be achieved. The expected performance of a full-scale TORCH detector for the Upgrade II of the LHCb experiment is also discussed.
       
  • A State of the art current-septum dipole magnet
    • Abstract: Publication date: Available online 7 December 2018Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentAuthor(s): N. Tsoupas, K. Brown, F. Méot, C. Pearson, P. Pile, V. Ptitsyn, A. Rusek The acceleration process of charged particle beams often requires the use of few acceleration stages to provide the beam with the desired energy. The extraction of the beam from one acceleration stage and the injection to the next, both require a special type of magnet which comes under the name septum magnet. Such a magnet generates a strong field in one region and a very low field in another region with the two regions separated by a very thin material (septum). The septum thickness of such a magnet should be as thin as possible to reduce the strength of other devices, like kickers, which are involved in the extraction or injection processes. A thin septum is also advantageous during the slow beam extraction process to reduce the beam losses at the septum. One of the methods which in theory can generate very large differences in field strength in adjacent field regions separated by a thin septum, is the use of two thin parallel current sheets of infinite dimensions. In practice we use other devices that can approximate such an abrupt change of the magnetic field within the septum thickness. In this paper we describe such a device, the DC current septum, we present results from the study of its electromagnetic properties, and we discuss a method to minimize the magnetic field in the region which requires a very small magnetic field. We also provide some results from the experimental measurements of the magnetic field generated by the “D6” current septum magnet which is installed in the experimental beam line of the NASA’s Space Radiation Laboratory (NSRL) facility (Tsoupas et al., 2007 ; Brown et al., 2010) at Brookhaven National Laboratory (BNL). This septum magnet is part of the beam’s extraction system from the AGS-Booster into the NSRL beam line for material and biological studies.
       
 
 
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