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Publisher: Springer-Verlag (Total: 2352 journals)

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Showing 1 - 200 of 2352 Journals sorted alphabetically
3D Research     Hybrid Journal   (Followers: 17, SJR: 0.214, h-index: 10)
4OR: A Quarterly J. of Operations Research     Hybrid Journal   (Followers: 10, SJR: 1.073, h-index: 25)
AAPS J.     Hybrid Journal   (Followers: 20, SJR: 1.192, h-index: 74)
AAPS PharmSciTech     Hybrid Journal   (Followers: 6, SJR: 0.718, h-index: 54)
Abdominal Imaging     Hybrid Journal   (Followers: 14, SJR: 0.723, h-index: 60)
Abhandlungen aus dem Mathematischen Seminar der Universitat Hamburg     Hybrid Journal   (Followers: 3, SJR: 0.447, h-index: 12)
Academic Psychiatry     Full-text available via subscription   (Followers: 23, SJR: 0.492, h-index: 32)
Academic Questions     Hybrid Journal   (Followers: 8, SJR: 0.135, h-index: 6)
Accreditation and Quality Assurance: J. for Quality, Comparability and Reliability in Chemical Measurement     Hybrid Journal   (Followers: 26, SJR: 0.378, h-index: 30)
Acoustical Physics     Hybrid Journal   (Followers: 11, SJR: 0.355, h-index: 20)
Acoustics Australia     Hybrid Journal  
Acta Analytica     Hybrid Journal   (Followers: 7, SJR: 0.387, h-index: 6)
Acta Applicandae Mathematicae     Hybrid Journal   (Followers: 1, SJR: 0.624, h-index: 34)
Acta Biotheoretica     Hybrid Journal   (Followers: 5, SJR: 0.419, h-index: 25)
Acta Diabetologica     Hybrid Journal   (Followers: 14, SJR: 1.318, h-index: 46)
Acta Endoscopica     Hybrid Journal   (Followers: 1, SJR: 0.113, h-index: 8)
acta ethologica     Hybrid Journal   (Followers: 4, SJR: 0.465, h-index: 23)
Acta Geochimica     Hybrid Journal   (Followers: 5)
Acta Geodaetica et Geophysica     Hybrid Journal   (Followers: 1, SJR: 0.294, h-index: 13)
Acta Geotechnica     Hybrid Journal   (Followers: 7, SJR: 1.818, h-index: 22)
Acta Informatica     Hybrid Journal   (Followers: 5, SJR: 0.524, h-index: 32)
Acta Mathematica     Hybrid Journal   (Followers: 11, SJR: 8.021, h-index: 47)
Acta Mathematica Hungarica     Hybrid Journal   (Followers: 2, SJR: 0.53, h-index: 29)
Acta Mathematica Sinica, English Series     Hybrid Journal   (Followers: 6, SJR: 0.406, h-index: 30)
Acta Mathematica Vietnamica     Hybrid Journal   (SJR: 0.451, h-index: 5)
Acta Mathematicae Applicatae Sinica, English Series     Hybrid Journal   (SJR: 0.22, h-index: 20)
Acta Mechanica     Hybrid Journal   (Followers: 20, SJR: 0.898, h-index: 52)
Acta Mechanica Sinica     Hybrid Journal   (Followers: 5, SJR: 0.426, h-index: 29)
Acta Metallurgica Sinica (English Letters)     Hybrid Journal   (Followers: 5, SJR: 0.525, h-index: 18)
Acta Meteorologica Sinica     Hybrid Journal   (Followers: 3, SJR: 0.524, h-index: 14)
Acta Neurochirurgica     Hybrid Journal   (Followers: 7, SJR: 0.833, h-index: 73)
Acta Neurologica Belgica     Hybrid Journal   (Followers: 1, SJR: 0.348, h-index: 27)
Acta Neuropathologica     Hybrid Journal   (Followers: 5, SJR: 6.61, h-index: 117)
Acta Oceanologica Sinica     Hybrid Journal   (Followers: 3, SJR: 0.295, h-index: 17)
Acta Parasitologica     Hybrid Journal   (Followers: 9, SJR: 0.581, h-index: 28)
Acta Physiologiae Plantarum     Hybrid Journal   (Followers: 2, SJR: 0.551, h-index: 39)
Acta Politica     Hybrid Journal   (Followers: 13, SJR: 0.658, h-index: 20)
Activitas Nervosa Superior     Hybrid Journal  
adhäsion KLEBEN & DICHTEN     Hybrid Journal   (Followers: 5, SJR: 0.103, h-index: 4)
ADHD Attention Deficit and Hyperactivity Disorders     Hybrid Journal   (Followers: 22, SJR: 0.871, h-index: 15)
Adhesion Adhesives & Sealants     Hybrid Journal   (Followers: 8)
Administration and Policy in Mental Health and Mental Health Services Research     Partially Free   (Followers: 15, SJR: 0.795, h-index: 40)
Adsorption     Hybrid Journal   (Followers: 4, SJR: 0.774, h-index: 52)
Advances in Applied Clifford Algebras     Hybrid Journal   (Followers: 3, SJR: 0.319, h-index: 15)
Advances in Atmospheric Sciences     Hybrid Journal   (Followers: 34, SJR: 0.959, h-index: 44)
Advances in Computational Mathematics     Hybrid Journal   (Followers: 15, SJR: 1.255, h-index: 44)
Advances in Contraception     Hybrid Journal   (Followers: 3)
Advances in Data Analysis and Classification     Hybrid Journal   (Followers: 51, SJR: 1.113, h-index: 14)
Advances in Gerontology     Partially Free   (Followers: 8, SJR: 0.141, h-index: 3)
Advances in Health Sciences Education     Hybrid Journal   (Followers: 22, SJR: 1.397, h-index: 42)
Advances in Manufacturing     Hybrid Journal   (Followers: 3, SJR: 0.2, h-index: 4)
Advances in Polymer Science     Hybrid Journal   (Followers: 41, SJR: 0.637, h-index: 89)
Advances in Therapy     Hybrid Journal   (Followers: 5, SJR: 0.79, h-index: 44)
Aegean Review of the Law of the Sea and Maritime Law     Hybrid Journal   (Followers: 7)
Aequationes Mathematicae     Hybrid Journal   (Followers: 2, SJR: 0.882, h-index: 23)
Aerobiologia     Hybrid Journal   (Followers: 1, SJR: 0.511, h-index: 36)
Aesthetic Plastic Surgery     Hybrid Journal   (Followers: 9, SJR: 0.821, h-index: 49)
African Archaeological Review     Hybrid Journal   (Followers: 15, SJR: 0.612, h-index: 24)
Afrika Matematika     Hybrid Journal   (Followers: 1, SJR: 0.248, h-index: 6)
AGE     Hybrid Journal   (Followers: 7, SJR: 1.358, h-index: 33)
Ageing Intl.     Hybrid Journal   (Followers: 7, SJR: 0.337, h-index: 10)
Aggiornamenti CIO     Hybrid Journal   (Followers: 1)
Aging Clinical and Experimental Research     Hybrid Journal   (Followers: 3, SJR: 0.529, h-index: 55)
Agricultural Research     Hybrid Journal   (Followers: 3)
Agriculture and Human Values     Hybrid Journal   (Followers: 13, SJR: 1.197, h-index: 49)
Agroforestry Systems     Hybrid Journal   (Followers: 19, SJR: 0.64, h-index: 56)
Agronomy for Sustainable Development     Hybrid Journal   (Followers: 10, SJR: 1.732, h-index: 59)
AI & Society     Hybrid Journal   (Followers: 7, SJR: 0.171, h-index: 19)
AIDS and Behavior     Hybrid Journal   (Followers: 13, SJR: 2.006, h-index: 71)
Air Quality, Atmosphere & Health     Hybrid Journal   (Followers: 4, SJR: 0.706, h-index: 19)
Akupunktur & Aurikulomedizin     Full-text available via subscription   (Followers: 1)
Algebra and Logic     Hybrid Journal   (Followers: 4, SJR: 0.566, h-index: 18)
Algebra Universalis     Hybrid Journal   (Followers: 2, SJR: 0.388, h-index: 22)
Algebras and Representation Theory     Hybrid Journal   (Followers: 1, SJR: 0.868, h-index: 20)
Algorithmica     Hybrid Journal   (Followers: 8, SJR: 0.898, h-index: 56)
Allergo J.     Full-text available via subscription   (Followers: 1, SJR: 0.183, h-index: 20)
Allergo J. Intl.     Hybrid Journal   (Followers: 2)
Alpine Botany     Hybrid Journal   (Followers: 5, SJR: 0.729, h-index: 20)
ALTEX : Alternatives to Animal Experimentation     Open Access   (Followers: 3, SJR: 1.392, h-index: 32)
AMBIO     Hybrid Journal   (Followers: 15, SJR: 1.094, h-index: 87)
American J. of Cardiovascular Drugs     Hybrid Journal   (Followers: 15, SJR: 0.864, h-index: 39)
American J. of Community Psychology     Hybrid Journal   (Followers: 24, SJR: 1.237, h-index: 83)
American J. of Criminal Justice     Hybrid Journal   (Followers: 7, SJR: 0.634, h-index: 13)
American J. of Cultural Sociology     Hybrid Journal   (Followers: 12, SJR: 0.283, h-index: 3)
American J. of Dance Therapy     Hybrid Journal   (Followers: 4, SJR: 0.175, h-index: 13)
American J. of Potato Research     Hybrid Journal   (Followers: 2, SJR: 0.558, h-index: 35)
American J. of Psychoanalysis     Hybrid Journal   (Followers: 22, SJR: 0.293, h-index: 13)
American Sociologist     Hybrid Journal   (Followers: 14, SJR: 0.18, h-index: 13)
Amino Acids     Hybrid Journal   (Followers: 8, SJR: 1.362, h-index: 83)
AMS Review     Partially Free   (Followers: 4)
Analog Integrated Circuits and Signal Processing     Hybrid Journal   (Followers: 7, SJR: 0.21, h-index: 37)
Analysis and Mathematical Physics     Hybrid Journal   (Followers: 3, SJR: 0.665, h-index: 7)
Analysis in Theory and Applications     Hybrid Journal   (Followers: 1)
Analysis of Verbal Behavior     Hybrid Journal   (Followers: 5)
Analytical and Bioanalytical Chemistry     Hybrid Journal   (Followers: 31, SJR: 1.096, h-index: 123)
Anatomical Science Intl.     Hybrid Journal   (Followers: 2, SJR: 0.301, h-index: 26)
Angewandte Schmerztherapie und Palliativmedizin     Hybrid Journal  
Angiogenesis     Hybrid Journal   (Followers: 3, SJR: 2.212, h-index: 69)
Animal Cognition     Hybrid Journal   (Followers: 16, SJR: 1.122, h-index: 55)
Annales françaises de médecine d'urgence     Hybrid Journal   (Followers: 1, SJR: 0.156, h-index: 4)
Annales Henri Poincaré     Hybrid Journal   (Followers: 3, SJR: 1.377, h-index: 32)
Annales mathématiques du Québec     Hybrid Journal   (Followers: 4)
Annali dell'Universita di Ferrara     Hybrid Journal   (SJR: 0.504, h-index: 14)
Annali di Matematica Pura ed Applicata     Hybrid Journal   (Followers: 1, SJR: 1.167, h-index: 26)
Annals of Behavioral Medicine     Hybrid Journal   (Followers: 11, SJR: 2.112, h-index: 98)
Annals of Biomedical Engineering     Hybrid Journal   (Followers: 18, SJR: 1.182, h-index: 94)
Annals of Combinatorics     Hybrid Journal   (Followers: 3, SJR: 0.849, h-index: 15)
Annals of Data Science     Hybrid Journal   (Followers: 11)
Annals of Dyslexia     Hybrid Journal   (Followers: 9, SJR: 0.857, h-index: 40)
Annals of Finance     Hybrid Journal   (Followers: 28, SJR: 0.686, h-index: 14)
Annals of Forest Science     Hybrid Journal   (Followers: 6, SJR: 0.929, h-index: 57)
Annals of Global Analysis and Geometry     Hybrid Journal   (Followers: 1, SJR: 1.136, h-index: 23)
Annals of Hematology     Hybrid Journal   (Followers: 14, SJR: 1.117, h-index: 62)
Annals of Mathematics and Artificial Intelligence     Hybrid Journal   (Followers: 7, SJR: 0.593, h-index: 42)
Annals of Microbiology     Hybrid Journal   (Followers: 10, SJR: 0.402, h-index: 26)
Annals of Nuclear Medicine     Hybrid Journal   (Followers: 5, SJR: 0.68, h-index: 45)
Annals of Operations Research     Hybrid Journal   (Followers: 8, SJR: 1.186, h-index: 78)
Annals of Ophthalmology     Hybrid Journal   (Followers: 12)
Annals of Regional Science     Hybrid Journal   (Followers: 7, SJR: 0.405, h-index: 42)
Annals of Software Engineering     Hybrid Journal   (Followers: 13)
Annals of Solid and Structural Mechanics     Hybrid Journal   (Followers: 10, SJR: 0.553, h-index: 8)
Annals of Surgical Oncology     Hybrid Journal   (Followers: 15, SJR: 1.902, h-index: 127)
Annals of Telecommunications     Hybrid Journal   (Followers: 7, SJR: 0.315, h-index: 25)
Annals of the Institute of Statistical Mathematics     Hybrid Journal   (Followers: 1, SJR: 0.931, h-index: 31)
Antonie van Leeuwenhoek     Hybrid Journal   (Followers: 5, SJR: 0.992, h-index: 87)
Apidologie     Hybrid Journal   (Followers: 4, SJR: 1.14, h-index: 57)
APOPTOSIS     Hybrid Journal   (Followers: 8, SJR: 1.554, h-index: 87)
Applicable Algebra in Engineering, Communication and Computing     Hybrid Journal   (Followers: 2, SJR: 0.354, h-index: 27)
Applications of Mathematics     Hybrid Journal   (Followers: 1, SJR: 0.274, h-index: 20)
Applied Biochemistry and Biotechnology     Hybrid Journal   (Followers: 44, SJR: 0.575, h-index: 80)
Applied Biochemistry and Microbiology     Hybrid Journal   (Followers: 17, SJR: 0.267, h-index: 26)
Applied Cancer Research     Open Access  
Applied Categorical Structures     Hybrid Journal   (Followers: 2, SJR: 0.361, h-index: 21)
Applied Composite Materials     Hybrid Journal   (Followers: 48, SJR: 0.705, h-index: 35)
Applied Entomology and Zoology     Partially Free   (Followers: 3, SJR: 0.554, h-index: 34)
Applied Geomatics     Hybrid Journal   (Followers: 3, SJR: 0.323, h-index: 9)
Applied Geophysics     Hybrid Journal   (Followers: 8, SJR: 0.541, h-index: 13)
Applied Intelligence     Hybrid Journal   (Followers: 11, SJR: 0.777, h-index: 43)
Applied Magnetic Resonance     Hybrid Journal   (Followers: 4, SJR: 0.358, h-index: 34)
Applied Mathematics & Optimization     Hybrid Journal   (Followers: 4, SJR: 0.955, h-index: 33)
Applied Mathematics - A J. of Chinese Universities     Hybrid Journal   (SJR: 0.275, h-index: 8)
Applied Mathematics and Mechanics     Hybrid Journal   (Followers: 5, SJR: 0.37, h-index: 26)
Applied Microbiology and Biotechnology     Hybrid Journal   (Followers: 62, SJR: 1.262, h-index: 161)
Applied Physics A     Hybrid Journal   (Followers: 7, SJR: 0.535, h-index: 121)
Applied Physics B: Lasers and Optics     Hybrid Journal   (Followers: 23, SJR: 0.983, h-index: 104)
Applied Psychophysiology and Biofeedback     Hybrid Journal   (Followers: 8, SJR: 0.677, h-index: 47)
Applied Research in Quality of Life     Hybrid Journal   (Followers: 11, SJR: 0.288, h-index: 15)
Applied Solar Energy     Hybrid Journal   (Followers: 17, SJR: 0.251, h-index: 6)
Applied Spatial Analysis and Policy     Hybrid Journal   (Followers: 4, SJR: 0.351, h-index: 9)
Aquaculture Intl.     Hybrid Journal   (Followers: 22, SJR: 0.613, h-index: 40)
Aquarium Sciences and Conservation     Hybrid Journal   (Followers: 1)
Aquatic Ecology     Hybrid Journal   (Followers: 32, SJR: 0.646, h-index: 44)
Aquatic Geochemistry     Hybrid Journal   (Followers: 4, SJR: 0.764, h-index: 39)
Aquatic Sciences     Hybrid Journal   (Followers: 13, SJR: 1.172, h-index: 53)
Arabian J. for Science and Engineering     Hybrid Journal   (Followers: 5, SJR: 0.345, h-index: 20)
Arabian J. of Geosciences     Hybrid Journal   (Followers: 1, SJR: 0.417, h-index: 16)
Archaeological and Anthropological Sciences     Hybrid Journal   (Followers: 23, SJR: 1.056, h-index: 15)
Archaeologies     Hybrid Journal   (Followers: 12, SJR: 0.397, h-index: 13)
Archiv der Mathematik     Hybrid Journal   (Followers: 1, SJR: 0.597, h-index: 29)
Archival Science     Hybrid Journal   (Followers: 56, SJR: 0.804, h-index: 22)
Archive for History of Exact Sciences     Hybrid Journal   (Followers: 8, SJR: 0.28, h-index: 15)
Archive for Mathematical Logic     Hybrid Journal   (Followers: 1, SJR: 0.946, h-index: 23)
Archive for Rational Mechanics and Analysis     Hybrid Journal   (SJR: 4.091, h-index: 66)
Archive of Applied Mechanics     Hybrid Journal   (Followers: 5, SJR: 0.865, h-index: 40)
Archives and Museum Informatics     Hybrid Journal   (Followers: 133)
Archives of Computational Methods in Engineering     Hybrid Journal   (Followers: 4, SJR: 2.841, h-index: 40)
Archives of Dermatological Research     Hybrid Journal   (Followers: 7, SJR: 0.9, h-index: 65)
Archives of Environmental Contamination and Toxicology     Hybrid Journal   (Followers: 11, SJR: 0.846, h-index: 84)
Archives of Gynecology and Obstetrics     Hybrid Journal   (Followers: 17, SJR: 0.695, h-index: 47)
Archives of Microbiology     Hybrid Journal   (Followers: 8, SJR: 0.702, h-index: 85)
Archives of Orthopaedic and Trauma Surgery     Hybrid Journal   (Followers: 8, SJR: 1.039, h-index: 56)
Archives of Osteoporosis     Hybrid Journal   (Followers: 2, SJR: 1.092, h-index: 13)
Archives of Sexual Behavior     Hybrid Journal   (Followers: 9, SJR: 1.198, h-index: 74)
Archives of Toxicology     Hybrid Journal   (Followers: 16, SJR: 1.595, h-index: 76)
Archives of Virology     Hybrid Journal   (Followers: 5, SJR: 1.086, h-index: 90)
Archives of Women's Mental Health     Hybrid Journal   (Followers: 14, SJR: 1.264, h-index: 50)
Archivio di Ortopedia e Reumatologia     Hybrid Journal  
Archivum Immunologiae et Therapiae Experimentalis     Hybrid Journal   (Followers: 2, SJR: 1.2, h-index: 42)
ArgoSpine News & J.     Hybrid Journal   (SJR: 0.102, h-index: 3)
Argumentation     Hybrid Journal   (Followers: 5, SJR: 0.295, h-index: 18)
Arid Ecosystems     Hybrid Journal   (Followers: 3)
Arkiv för Matematik     Hybrid Journal   (Followers: 1, SJR: 0.948, h-index: 22)
Arnold Mathematical J.     Hybrid Journal   (Followers: 1)
Arthropod-Plant Interactions     Hybrid Journal   (Followers: 2, SJR: 0.797, h-index: 17)
Arthroskopie     Hybrid Journal   (Followers: 1, SJR: 0.145, h-index: 8)
Artificial Intelligence and Law     Hybrid Journal   (Followers: 10, SJR: 0.288, h-index: 25)
Artificial Intelligence Review     Hybrid Journal   (Followers: 14, SJR: 0.948, h-index: 48)
Artificial Life and Robotics     Hybrid Journal   (Followers: 8, SJR: 0.231, h-index: 14)
Asia Europe J.     Hybrid Journal   (Followers: 5, SJR: 0.247, h-index: 9)
Asia Pacific Education Review     Hybrid Journal   (Followers: 12, SJR: 0.371, h-index: 17)
Asia Pacific J. of Management     Hybrid Journal   (Followers: 15, SJR: 1.676, h-index: 50)
Asia-Pacific Education Researcher     Hybrid Journal   (Followers: 12, SJR: 0.353, h-index: 13)
Asia-Pacific Financial Markets     Hybrid Journal   (Followers: 2, SJR: 0.19, h-index: 15)
Asia-Pacific J. of Atmospheric Sciences     Hybrid Journal   (Followers: 20, SJR: 1.006, h-index: 14)
Asian Business & Management     Hybrid Journal   (Followers: 8, SJR: 0.41, h-index: 10)
Asian J. of Business Ethics     Hybrid Journal   (Followers: 7)
Asian J. of Criminology     Hybrid Journal   (Followers: 5, SJR: 0.263, h-index: 8)
AStA Advances in Statistical Analysis     Hybrid Journal   (Followers: 2, SJR: 0.681, h-index: 15)
AStA Wirtschafts- und Sozialstatistisches Archiv     Hybrid Journal   (Followers: 5, SJR: 0.195, h-index: 5)
ästhetische dermatologie & kosmetologie     Full-text available via subscription  

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Journal Cover Astronomy Reports
  [SJR: 0.473]   [H-I: 23]   [12 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 1562-6881 - ISSN (Online) 1063-7729
   Published by Springer-Verlag Homepage  [2352 journals]
  • Galactic orbits of selected companions of the Milky Way
    • Authors: A. T. Bajkova; V. V. Bobylev
      Pages: 727 - 738
      Abstract: High-accuracy absolute proper motions, radial velocities, and distances have now been measured for a number of dwarf-galaxy companions of the Milky Way, making it possible to study their 3D dynamics. Galactic orbits for 11 such galaxies (Fornax, Sagittarius, Ursa Minor, LMC, SMC, Sculptor, Sextans, Carina, Draco, Leo I, Leo II) have been derived using two previously refined models for the Galactic potential with the Navarro–Frenk–White and Allen–Santillán expressions for the potential of the dark-matter halo, and two different masses for the Galaxy within 200 kpc—0.75 × 1012 M ⊙ and 1.45 × 1012 M ⊙. The character of the orbits of most of these galaxies indicates that they are tightly gravitationally bound to the Milky Way, even with the lower-mass model for the gravitational potential. One exception is the most distant galaxy in the list, Leo I, whose orbit demonstrates that it is only weakly gravitationally bound, even using the higher-mass model of the gravitational potential.
      PubDate: 2017-09-01
      DOI: 10.1134/s1063772917080017
      Issue No: Vol. 61, No. 9 (2017)
       
  • A dynamo in a torus as an explanation of magnetic fields in the outer
           rings of galaxies
    • Authors: E. A. Mikhailov
      Pages: 739 - 746
      Abstract: It is currently generally believed that magnetic fields in the disks of spiral galaxies are generated by the dynamo mechanism, which is based on the joint action of differential rotation and the alpha effect, associated with turbulent motions in the interstellar gas. Together with their disks, outer rings are also encountered in galaxies, where magnetic fields may be present. In earlier studies, the generation of magnetic fields has been described in a planar approximation, whose essence is that the size of rings perpendicular to the plane of the galaxy is much smaller than their size in the radial direction. However, it is plausible that these sizesmay sometimes be comparable, so that it would be more logical to suppose that a ring has a toroidal form. A model for a dynamo in a toroidal ring is constructed in this study. This model describes the magnetic field using two functions, corresponding to the toroidal component of the field and the part of the vector potential characterizing its poloidal component. The possible generation of magnetic field in various cases is shown, with both quadrupolar symmetry (close to the fields obtained in the planar approximation) and dipolar symmetry (when two layers with oppositely directed magnetic fields form in the ring). The parameter values for which the generation of fields with one or the other type of symmetry is possible are estimated. The results can also be used to describe the evolution of the magnetic fields in other toroidal astrophysical objects.
      PubDate: 2017-09-01
      DOI: 10.1134/s1063772917080078
      Issue No: Vol. 61, No. 9 (2017)
       
  • Observations of giant pulses from B1237+25 (J1239+2453) at 111 MHz.
           Detection and classification
    • Authors: A. N. Kazantsev; V. A. Potapov
      Pages: 747 - 759
      Abstract: An analysis of data from monitoring of individual pulses of the second-period pulsar PSR B1237+25 (J1239+2453) carried out on the Large Phased Array (LPA) of the Pushchino Radio Astronomy Observatory at 111 MHz during 2012–2015 is presented. The aim of this observing program is a search for anomalously strong and giant pulses. The regular generation of powerful individual pulses at the longitudes of three of five components in the main profile of PSR B1237+25 has been detected. The distribution of these strong pulses in flux density is bimodal, and has the power-law form characteristic for giant pulses, with power-law indices n = −1.26 ± 0.05 and −3.36 ± 0.34, which differentiates them from the regular pulses of pulsars, having a log–normal distribution. The characteristic pulse widths at the half-intensity level are 3–5 ms, which comprises 50–100% of the width of the corresponding component in the mean profile. The most powerful of the detected pulses had a peak flux density of 900 ± 160 Jy, and the strongest pulse exceeded the session-mean profile by a factor of 65.
      PubDate: 2017-09-01
      DOI: 10.1134/s1063772917080054
      Issue No: Vol. 61, No. 9 (2017)
       
  • Gas kinematics in high-mass star-forming regions from the Perseus spiral
           arm
    • Authors: M. S. Kirsanova; A. M. Sobolev; M. Thomasson
      Pages: 760 - 774
      Abstract: We present results of a survey of 14 star-forming regions from the Perseus spiral armin CS (2–1) and 13CO (1–0) lines with the Onsala Space Observatory 20 m telescope. Maps of 10 sources in both lines are obtained. For the remaining sources a map in just one line or a single-point spectrum is obtained. On the basis of newly obtained and published observational data we consider the relation between velocities of the “quasi-thermal” CS (2–1) line and 6.7 GHz methanol maser line in 24 high-mass star-forming regions in the Perseus arm. We show that, surprisingly, velocity ranges of 6.7 GHz methanol maser emission are predominantly red-shifted with respect to corresponding CS (2–1) line velocity ranges in the Perseus arm. We suggest that the predominance of the “red-shifted masers” in the Perseus arm could be related to the alignment of gas flows caused by the large-scalemotions in the Galaxy. Large-scale galactic shock related to the spiral structure is supposed to affect the local kinematics of the star-forming regions. Part of the Perseus arm, between galactic longitudes from 85° to 124° , does not contain blue-shifted masers at all. Radial velocities of the sources are the greatest in this particular part of the arm, so the velocity difference is clearly pronounced. 13CO (1–0) and CS (2–1) velocity maps of G183.35-0.58 show gas velocity difference between the center and the periphery of the molecular clump up to 1.2 km s−1. Similar situation is likely to occur in G85.40-0.00. This can correspond to the case when the large-scale shock wave entrains the outer parts of a molecular clump in motion while the dense central clump is less affected by the shock.
      PubDate: 2017-09-01
      DOI: 10.1134/s1063772917090025
      Issue No: Vol. 61, No. 9 (2017)
       
  • Localization of the magnetic field in a plasma flow in laboratory
           simulations of astrophysical jets at the KPF-4-PHOENIX installation
    • Authors: K. N. Mitrofanov; S. S. Anan’ev; D. A. Voitenko; V. I. Krauz; G. I. Astapenko; A. I. Markoliya; V. V. Myalton
      Pages: 775 - 782
      Abstract: The results of experiments aimed at investigating axial plasma flows forming during the compression of a current–plasma sheath are presented. These experiments were carried out at the KPF-4-PHOENIX plasma-focus installation, as part of a program of laboratory simulations of astrophysical jets. The plasma flows were generated in a discharge when the chamber was filled with the working gas (argon) at initial pressures of 0.5–2 Torr. Experimental data obtained using a magnetic probe and optical diagnostics are compared. The data obtained can be used to determine the location of trapped magnetic field relative to regions of intense optical glow in the plasma flow.
      PubDate: 2017-09-01
      DOI: 10.1134/s106377291708008x
      Issue No: Vol. 61, No. 9 (2017)
       
  • The anisotropy of kinetic and current helicity
    • Authors: M. Yu. Reshetnyak
      Pages: 783 - 790
      Abstract: A three-dimensional model for thermal convection with a dynamo in a rotating planar layer heated from below is used to investigate the behavior of the mean kinetic and current helicities. In spite of the presence of gravity and rotation, which introduce anisotropy into the system, the components of the helicity determined from the field components in the directions tangent and normal to the boundary have similar values. The existence of a separation by scale, when the current helicity has different signs on different spatial scales, is demonstrated. The number of regions where the sign of the helicity does not coincide with the sign of its mean value in that region is estimated (∼43−45% of the total number of regions). The estimates presented are relevant for interpretations of observations of solar activity and analysis of the properties of rotating magnetohydrodynamical turbulence.
      PubDate: 2017-09-01
      DOI: 10.1134/s1063772917080108
      Issue No: Vol. 61, No. 9 (2017)
       
  • Catalog of hard X-ray solar flares detected with Mars Odyssey/HEND from
           the Mars orbit in 2001–2016
    • Authors: M. A. Livshits; I. V. Zimovets; D. V. Golovin; B. A. Nizamov; V. I. Vybornov; I. G. Mitrofanov; A. S. Kozyrev; M. L. Litvak; A. B. Sanin; V. I. Tretyakov
      Pages: 791 - 804
      Abstract: The study of nonstationary processes in the Sun is of great interest, and multi-wavelength observations and the registration of magnetic fields have been carried out using both ground-based telescopes and several specialized spacecraft in near-Earth orbits in recent years. However, the acquisition of new, reliable information on their hard X-ray radiation remains necessary, in particular, if the corresponding spacecraft provide additional information, e.g., in regard to flare observations from directions other than the Sun–Earth direction. This paper presents a catalog of powerful solar flares registered by the High Energy Neutron Detector (HEND) designed at the Space Research Institute of the Russian Academy of Sciences. HEND is mounted onboard the 2001Mars Odyssey spacecraft. It operated successfully during the flight to Mars and is currently operating in near-Mars orbit. Apart from neutrons, HEND is sensitive to hard X-ray (up to 300 keV) and gamma-ray radiation (above 300 keV). This radiation is registered by two scintillators: an outer one that is sensitive to photons above 40 keV and an inner one sensitive to photons above 200 keV. The catalog was created using a new procedure for calibration of the data. For the most powerful 60 solar flares in the visible and far sides of the Sun (for a terrestrial observer), time profiles of the flare radiation summed over all channels of the X-ray, and in some cases the gamma-ray, bands are provided, as well as spectra and characteristics of power-law fits. The results of previous studies of the Sun using HEND and the potential for further use of these data are discussed.
      PubDate: 2017-09-01
      DOI: 10.1134/s1063772917090037
      Issue No: Vol. 61, No. 9 (2017)
       
  • Evidence for shock generation in the solar corona in the absence of
           coronal mass ejections
    • Authors: V. G. Eselevich; M. V. Eselevich; I. V. Zimovets; I. N. Sharykin
      Pages: 805 - 819
      Abstract: The solar event SOL2012–10–23T03:13, which was associated with a X1.8 flare without an accompanying coronal mass ejection (CME) and with a Type II radio burst, is analyzed. A method for constructing the spatial and temporal profiles of the difference brightness detected in the AIA/SDOUVand EUV channels is used together with the analysis of the Type II radio burst. The formation and propagation of a region of compression preceded by a collisional shock detected at distances R < 1.3R ⊙ from the center of the Sun is observed in this event (R ⊙ is the solar radius). Comparison with a similar event studied earlier, SOL2011–02–28T07:34 [1], suggests that the region of compression and shock could be due to a transient (impulsive) action exerted on the surrounding plasma by an eruptive, high-temperature magnetic rope. The initial instability and eruption of this rope could be initiated by emerging magnetic flux, and its heating from magnetic reconnection. The cessation of the eruption of the rope could result from its interaction with surrounding magnetic structures (coronal loops).
      PubDate: 2017-09-01
      DOI: 10.1134/s1063772917080030
      Issue No: Vol. 61, No. 9 (2017)
       
  • The high-resolution Echelle Spectrograph of the 6-m telescope of the
           special astrophysical observatory
    • Authors: V. E. Panchuk; V. G. Klochkova; M. V. Yushkin
      Pages: 820 - 831
      Abstract: Results of the development and implementation of the Nasmyth Echelle Spectrograph (NES) of the 6-m telescope of the Special AstrophysicalObservatory are presented. The NES is a tunable spectral system with a large-diameter collimated beam that is suitable for various types of observations. Selected scientific programs carried out by the developers of the instrument are described as illustrations of its application. The possible development of the spectrograph with the 6-m telescope over the coming 19 years is discussed.
      PubDate: 2017-09-01
      DOI: 10.1134/s1063772917080091
      Issue No: Vol. 61, No. 9 (2017)
       
  • Indirect perturbation influence of planets on the variation of the
           instantaneous angular velocity of the rigid Earth in the lunar-solar
           gravitational field
    • Authors: Lin-Sen Li
      Pages: 702 - 708
      Abstract: The differential equation and its solution for indirect influence of the planetary perturbation on the variation of the rotational angular velocity of the rigid Earth in the lunar-solar gravitational field are obtained by using Euler’s dynamic equations. The theoretical results show that the angular velocity of the Earth varies with the periodic and mixed periodic variation under the lunar and solar gravitational field due to the planetary perturbation on the Earth orbit. The numerical results for the amplitudes of the periodic terms and the coefficient of the mixed periodic terms are presented.
      PubDate: 2017-08-01
      DOI: 10.1134/s1063772917080066
      Issue No: Vol. 61, No. 8 (2017)
       
  • Deviation of the major axis of the inertia ellipsoid of the Moon from the
           direction toward the Earth
    • Authors: B. P. Kondratyev
      Pages: 709 - 714
      Abstract: It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T 3 = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″.
      PubDate: 2017-08-01
      DOI: 10.1134/s1063772917070046
      Issue No: Vol. 61, No. 8 (2017)
       
  • Analysis of the optics of the 2.5-m telescope of the Sternberg
           Astronomical Institute
    • Authors: S. A. Potanin; I. A. Gorbunov; A. V. Dodin; A. D. Savvin; B. S. Safonov; N. I. Shatsky
      Pages: 715 - 725
      Abstract: The results of alignment and acceptance tests of the optics system of the 2.5-m telescope installed at the Caucausus Mountain Observatory of the Sternberg Astronomical Institute in 2013–2015 are reported. The optical elements of the Ritchey–Chrétien system of the telescope were manufactured by REOSC (France). Measurements of aberrations were carried out using a specially manufactured Shack–Hartmann wavefront sensor. Adjustment of the load-distribution mechanisms of the primary mirror and automatic correction for bending of the structure have made it possible to achieve the target image quality at all operational positions of the telescope, corresponding to 80% of the energy being concentrated in a circle 0.3″ in diameter. Factory interferograms of the mirrors and methods for measuring their abberation using stellar images are presented.
      PubDate: 2017-08-01
      DOI: 10.1134/s106377291707006x
      Issue No: Vol. 61, No. 8 (2017)
       
  • Formation of close binary black holes merging due to gravitational-wave
           radiation
    • Authors: A. V. Tutukov; A. M. Cherepashchuk
      Pages: 833 - 847
      Abstract: The conditions for the formation of close-binary black-hole systems merging over the Hubble time due to gravitational-wave radiation are considered in the framework of current ideas about the evolution of massive close-binary systems. The original systems whose mergers were detected by LIGO consisted of main-sequence stars with masses of 30–100M ⊙. The preservation of the compactness of a binary black hole during the evolution of its components requires either the formation of a common envelope, probably also with a low initial abundance of metals, or the presence of a “kick”—a velocity obtained during a supernova explosion accompanied by the formation of a black hole. In principle, such a kick can explain the relatively low frequency of mergers of the components of close-binary stellar black holes, if the characteristic speed of the kick exceeds the orbital velocities of the system components during the supernova explosion. Another opportunity for the components of close-binary systems to approach each other is related to their possible motion in a dense molecular cloud.
      PubDate: 2017-10-01
      DOI: 10.1134/s1063772917100092
      Issue No: Vol. 61, No. 10 (2017)
       
  • Search for and detection of pulsars inmonitoring observations at 111 MHz
    • Authors: S. A. Tyul’bashev; V. S. Tyul’bashev; M. A. Kitaeva; A. I. Chernyshova; V. M. Malofeev; I. V. Chashei; V. I. Shishov; R. D. Dagkesamanskii; S. V. Klimenko; I. N. Nikitin; L. D. Nikitina
      Pages: 848 - 858
      Abstract: In the course of monitoring interplanetary scintillations of a large number of sources using the Big Scanning Antenna of the Lebedev Physical Institute, a search for pulsars with periods ≥0.4 s at declinations −9◦ < δ < 42◦ and right ascensions 0h < α < 24h was simultaneously carried out. The search was conducted using four years of observations carried out at 110.25MHz in six frequency channels making up a 2.5 MHz band and having a time resolution of 100 ms. The initial identification of pulsar candidates was done using Fourier power spectra averaged over the entire observational period; the pulsar candidates were then verified using observations with higher frequency and time resolution: 32 frequency channels and a time resolution of 12.5 ms. Eighteen new pulsars were discovered in the studied area, whose main characteristics are presented.
      PubDate: 2017-10-01
      DOI: 10.1134/s1063772917100109
      Issue No: Vol. 61, No. 10 (2017)
       
  • Orbital period variations of the eclipsing binaries TU Cnc, VZ Leo, and OS
           Ori
    • Authors: A. I. Khaliullina
      Pages: 859 - 870
      Abstract: Variations of the orbital periods of the eclipsing binaries TU Cnc, VZ Leo, and OS Ori are analyzed. Secular period decreases were earlier believed to occur in these systems. It is demonstrated that the period variations of TU Cnc can be represented using the light-time effect corresponding to the orbital motion of the eclipsing binary with a period of 78.6 years around the center ofmass of the triple system, with the mass of the third body being M 3 > 0.82M ⊙. With the same accuracy, the period variations of VZ Leo and OS Ori can be represented either solely using the light-time effect, or a superposition of a secular period decrease and the light-time effect. For VZ Leo, the period of the long-term orbit is 63.8 years in the former case and 67.9 years in the latter case. Similar masses for the third body are indicated in both cases: M 3 > 0.55M ⊙ and M 3 > 0.61M ⊙. For OS Ori, the period of the long-term orbit is 46 years and M 3 > 0.5M ⊙ in the former case, and the period is 36 years and M 3 > 0.6M ⊙ in the latter case.
      PubDate: 2017-10-01
      DOI: 10.1134/s1063772917100055
      Issue No: Vol. 61, No. 10 (2017)
       
  • Activity of an M4.5 hyades dwarf with a planetary system
    • Authors: E. S. Dmitrienko; I. S. Savanov
      Pages: 871 - 877
      Abstract: An analysis of the activity of the Hyades M4.5 dwarf EPIC 210490365, K2–25 (2MASS J04130560+1514520), based on observational data obtained with the Kepler Space Telescope is presented. This dwarf has a Neptune-type planet. The continuous evolution of active regions on the surface of K2–25 is traced over 70 days. The brightness changes of the star display a fairly stable nature. The rotation period of K2–25 is 1.878 ± 0.030 day. Maps of temperature inhomogeneities on the surface of K2–25 are constructed for 37 sets of observations. All these maps show concentrations of spots at two longitudes, with more active region having the larger area. The total spotted surface area S is, on average, 2.6% of the total visible surface of the star. The estimated differential rotation speed of the star is ΔΩ = 0.0071 ± 0.002 rad/day. The positions of K2–25 in S–age, S–rotation period, and S–Rossby number diagrams are consistent with the general trends of these dependences established earlier for M dwarfs. The derived Rossby number for K2–25, Ro = 0.36, is used to estimate the star’s X-ray luminosity to be log(R X) = −4.20.
      PubDate: 2017-10-01
      DOI: 10.1134/s1063772917090013
      Issue No: Vol. 61, No. 10 (2017)
       
  • Parity fluctuations in stellar dynamos
    • Authors: D. L. Moss; D. D. Sokoloff
      Pages: 878 - 882
      Abstract: Observations of the solar butterfly diagram from sunspot records suggest persistent fluctuations in parity, away from the overall, approximately dipolar pattern. A simple mean-field dynamo model is used with a solar-like rotation law and perturbed α effect. The parity of the magnetic field relative to the rotational equator can demonstrate can be described as resonance behavior, while the magnetic energy behaves in a more or less expected way. Possible applications of this effect are discussed in the context of various deviations of the solar magnetic field from dipolar symmetry, as reported from analyses of archival sunspot data. The model produces fluctuations in field parity, and hence in the butterfly diagram, that are consistent with observed fluctuaions in solar behavior.
      PubDate: 2017-10-01
      DOI: 10.1134/s1063772917100079
      Issue No: Vol. 61, No. 10 (2017)
       
  • Search for close stellar encounters with the solar system from data on
           nearby dwarfs
    • Authors: V. V. Bobylev
      Pages: 883 - 890
      Abstract: Trigonometric parallaxesmeasuredwith ground-based telescopes of the RECONS consortium as part of the CTIOPI program are used to search for stars that have either had an encounter with the solar system in the past or will have such an encounter in the future, at distances of less than a few parsecs. These are mainly low-mass dwarfs and subdwarfs of types M, L, and T currently at distances of less than 30 pc from the Sun. Six stars for which encounters with the solar orbit at distances of less than 1 pc are possible have been identified for the first time. For example, the minimum distance for the star **SOZ 3A will be 0.72 ± 0.11 pc at an epoch of 103 ± 44 thousand years in the future.
      PubDate: 2017-10-01
      DOI: 10.1134/s106377291710002x
      Issue No: Vol. 61, No. 10 (2017)
       
  • Morphological indictors of the chirality of solar filaments
    • Authors: B. P. Filippov
      Pages: 891 - 900
      Abstract: There is no doubt that the structural features of filaments reflect properties of their magnetic fields, such as chirality and helicity. However, the interpretation of some morphological features can lead to incorrect conclusions when the observing time is limited and the spatial resolution is insufficiently high. In spite of the relative constancy of their overall shapes, filaments are dynamical formations with inhomogeneities moving along the threads making them up. Therefore, it is possible to observe material concentrated not only in magnetic traps, but also along curved arcs. Difficulties often arise in determining the chirality of filaments with anomalous “barbs”; i.e., those whose jagged side is located on the opposite side of the axis compared to most (“normal”) filaments. A simple model is used to show that anomalous barbs can exist in an ordinary magnetic flux rope, with the threads of its fine structure oriented nearly perpendicular to its length. A careful analysis of images with the maximum available spatial resolution and with information about temporal dynamics, together with comparisons with observations in various spectral lines, can enable a correct determination of the chirality of filaments.
      PubDate: 2017-10-01
      DOI: 10.1134/s1063772917100043
      Issue No: Vol. 61, No. 10 (2017)
       
  • Helioseismic models of the sun with a low heavy element abundance
    • Authors: S. V. Ayukov; V. A. Baturin
      Pages: 901 - 913
      Abstract: Helioseismology and neutrino experiments probing the internal structure of the Sun have yieldedmuch information, such as the adiabatic elasticity index, density, and sound speed in the convective and radiative zones, the depth of the convective zone, and the flux of neutrinos from the core. The standard model of the Sun does not adequately reproduce these characteristics, with models with low heavy element contents (mass fraction of metals Z = 0.013 in the convective zone) deviating from the helioseismic data appreciably more strongly than models with high heavy element contents (Z = 0.018). However, a spectroscopic low Z value is supported by studies reconstructing the Γ 1 profile in the adiabatic part of the convective zone based on the oscillation frequencies. Models of the convective zone show a good agreement precisely for low Z values. This study attempts to construct a model for the Sun with low Z that satisfies the helioseismic constraints. This model requires changes in the p + p reaction cross section and the opacities in the radiative zone. In our view, the helioseismic result for the mass concentrated in the convective zone testifies that the p + p reaction cross section or the electron-screening coefficient in the solar core must be increased by several percent over the current values. This requires a comparatively small correction to the opacities (by less than 5%), in order to obtain a solar model with low Z that is in agreement with the results of helioseismology and the observed solar neutrino fluxes.
      PubDate: 2017-10-01
      DOI: 10.1134/s1063772917100018
      Issue No: Vol. 61, No. 10 (2017)
       
 
 
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