Authors:Christophe Royon, William d’Assignies D., Florian Gautier, Tommaso Isidori, Nicola Minafra, Alexander Novikov First page: 14 Abstract: We use fast silicon detectors and the fast sampling method originally developed for high energy physics for two applications: cosmic ray measurements in collaboration with NASA and dose measurements during flash beam cancer treatment. The cosmic ray measurement will benefit from the fast sampling method to measure the Bragg peak where the particle stops in the silicon detector and the dose measurement is performed by counting the number of particles that enter the detector. Citation: Instruments PubDate: 2023-03-23 DOI: 10.3390/instruments7020014 Issue No:Vol. 7, No. 2 (2023)
Authors:Victor Amador Diaz, Scott E. Snyder, Amy L. Vavere First page: 15 Abstract: Vacuum pump wear is the most prevalent failure mode of the IBA Synthera® automated radiochemistry system. Rebuilding or replacing the pump causes equipment downtime and increases the radiation exposure of the service personnel. We built a dedicated test device to assess new or rebuilt pumps prior to installation, thus reducing downtime and radiation exposure during repairs. The Testbed incorporates a microprocessor that actuates the pump, valves, and pressure sensor; communicates with the user through lights, buttons, and an alphanumeric screen; and outputs test results to a laptop. The Testbed increases productivity and safety in the radiochemistry laboratory. Citation: Instruments PubDate: 2023-04-06 DOI: 10.3390/instruments7020015 Issue No:Vol. 7, No. 2 (2023)
Authors:Frédéric Nolet, Valérie Gauthier, Samuel Parent, Frédéric Vachon, Nicolas Roy, Nicolas St-Jean, Serge A. Charlebois, Jean-François Pratte First page: 16 Abstract: In the field of radiation instrumentation, there is a desire to reach a sub-10 ps FWHM timing resolution for applications such as time-of-flight positron emission tomography, time-of-flight positron computed tomography and time-resolved calorimetry. One of the key parts of the detection chain for these applications is a single-photon detector and, in recent years, the first single-photon avalanche diode (SPAD) with a sub-10 ps timing resolution was presented. To reach such a timing resolution, the SPAD was read out by an operational amplifier operated in open-loop as a comparator. This paper presents a comparison between comparators and inverters to determine which type of leading-edge discriminator can obtain the best single-photon timing resolution. Six different quenching circuits (QCs) implemented in TSMC 65 nm are tested with SPADs of the same architecture and in the same operation conditions. This allows us to compare experimental results between the different QCs. This paper also presents a method to measure the SPAD signal slope, the SPAD excess voltage variation and simulations to determine the added jitter of different leading-edge discriminators. For some discriminator architectures, a cascode transistor was required to increase the maximum excess voltage of the QC. This paper also presents the impact on the single-photon timing resolution of adding a cascode transistor for a comparator or an inverter-based discriminator. This paper reports a 6.3 ps FWHM SPTR for a SPAD read out by a low-threshold comparator and a 6.8 ps FWHM SPTR for an optimized 1 V inverter using a cascode transistor for a higher excess voltage. Citation: Instruments PubDate: 2023-04-09 DOI: 10.3390/instruments7020016 Issue No:Vol. 7, No. 2 (2023)
Authors:David Joffe, Christian Perez First page: 17 Abstract: Muography requires a detailed understanding of the absorption of muons in the material situated between the muon source and the detector. A large-statistics (>3 billion event) Geant4 simulation was run to simulate the absorption of muons in different thicknesses of concrete layers and to determine the effect of the material on the energies of muons that were not absorbed. The Geant4 simulation included a simple detector placed directly behind the absorbing material. A Geant4 simulation was also run for the same detector for alpha sources with no absorbing material and the results of this simulation were compared to the signals from the physical detector built in the laboratory and measured using standard alpha sources. The large-statistics simulations using muons of different energies were compared to the predictions of muon absorption from existing literature. The results of the simulations were in good agreement with both the measured signals from the laboratory as well as the predictions from the literature and the general method is found to be well-suited for studies used for muography involving material layers of uniform thickness. Citation: Instruments PubDate: 2023-05-31 DOI: 10.3390/instruments7020017 Issue No:Vol. 7, No. 2 (2023)
Authors:Motoki Ishikawa, Kakuta Ishida, Reika Kanya, Kaoru Yamanouchi First page: 4 Abstract: We developed an apparatus for measuring kinetic energy and two-dimensional angular distributions of femtosecond laser-assisted electron scattering (LAES) signals with a high detection efficiency, consisting of a photocathode-type ultrashort pulsed electron gun, a gas injection nozzle, an angle-resolved time-of-flight analyzer, and a time-and-position sensitive electron detector. We also established an analysis method for obtaining the kinetic energy and two-dimensional angular distributions of scattered electrons from raw data of their flight times and the detected positions at the detector recorded using the newly developed apparatus. From the measurement of the LAES processes of Ar atoms in a femtosecond near-infrared intense laser field, we obtained a two-dimensional angular distribution image of the LAES signals and showed that the detection efficiency of the LAES signals was raised by a factor of 40 compared with that achieved before in 2010. Citation: Instruments PubDate: 2023-01-03 DOI: 10.3390/instruments7010004 Issue No:Vol. 7, No. 1 (2023)
Authors:Dayong Tai, Zhixiong Wu, Ying Yang, Cunwei Lu First page: 5 Abstract: The measurement system proposed in this paper, using a measuring arm and line structured light, has a wide range of applications. To improve the scanning efficiency, the system outlined in this paper uses two single-line structured lights to form crosshair structured light, which we combine with a measuring arm to form a comprehensive scanning measurement system. The calibration method of Zhengyou Zhang and a calibration board are used to complete parameter calibration of the sensors and cameras, as well as hand–eye calibration of the measuring arm. For complex curved-surface objects, this system extracts the cross-line structured light optical center location, which suffers from ambiguity. Therefore, we introduce the use of periodic control of the two line structured light sources in order to resolve the light extraction polysemy. Our experimental results indicate that the proposed system can effectively satisfy the function of crosshair structured light scanning of large, complex surfaces. Citation: Instruments PubDate: 2023-01-03 DOI: 10.3390/instruments7010005 Issue No:Vol. 7, No. 1 (2023)
Authors:Jesús Peña-Rodríguez, Juan Sánchez-Villafrades, Hernán Asorey, Luis A. Núñez First page: 7 Abstract: The Muon Telescope, MuTe, is an instrument for imaging volcanoes in Colombia. It consists of a scintillator tracking system and a water Cherenkov detector for particle energy measurement. The Muon Telescope operates autonomously in high-altitude environments where the temperature gradient reaches up to 10 ∘C. In this work, we characterize the telescope silicon photomultipliers’ breakdown voltage, gain, and noise for temperature variations spanning 0 to 40 ∘C. We demonstrate that the discrimination threshold for the Muon Telescope hodoscope must be above 5 photo-electrons to avoid contamination due to dark count, crosstalk, and afterpulsing. We also assess the detector counting rate depending on day-night temperature variations. Citation: Instruments PubDate: 2023-01-22 DOI: 10.3390/instruments7010007 Issue No:Vol. 7, No. 1 (2023)
Authors:Valerio Biancalana, Piero Chessa First page: 8 Abstract: We analyze the information that can be retrieved from the tracking parameters produced by an innovative wearable eye tracker. The latter is based on a permanent-magnet marked corneal lens and by an array of magnetoresistive detectors that measure the magnetostatic field in several positions in the eye proximity. We demonstrate that, despite missing information due to the axial symmetry of the measured field, physiological constraints or measurement conditions make possible to infer complete eye-pose data. Angular precision and accuracy achieved with the current prototypical device are also assessed and briefly discussed. The results show that the instrumentation considered is suitable as a new, moderately invasive medical diagnostics for the characterization of ocular movements and associated disorders. Citation: Instruments PubDate: 2023-02-07 DOI: 10.3390/instruments7010008 Issue No:Vol. 7, No. 1 (2023)
Authors:Alexander Dierlamm, Matthias Balzer, Felix Ehrler, Ulrich Husemann, Roland Koppenhöfer, Ivan Perić, Martin Pittermann, Bogdan Topko, Alena Weber, Stephan Brons, Jürgen Debus, Nicole Grau, Thomas Hansmann, Oliver Jäkel, Sebastian Klüter, Jakob Naumann First page: 9 Abstract: Particle therapy is a well established clinical treatment of tumors. More than one hundred particle therapy centers are in operation world-wide. The advantage of using hadrons like protons or carbon ions as particles for tumor irradiation is the distinct peak in the depth-dependent energy deposition, which can be exploited to accurately deposit doses in the tumor cells. To guarantee this, high accuracy in monitoring and control of the particle beam is of the utmost importance. Before the particle beam enters the patient, it traverses a monitoring system which has to give fast feedback to the beam control system on position and dose rate of the beam while minimally interacting with the beam. The multi-wire chambers mostly used as beam position monitors have their limitations when a fast response time is required (drift time). Future developments such as MRI-guided ion beam therapy pose additional challenges for the beam monitoring system, such as tolerance of magnetic fields and acoustic noise (vibrations). Solid-state detectors promise to overcome these limitations and the higher resolution they offer can create additional benefits. This article presents the evaluation of an HV-CMOS detector for beam monitoring, provides results from feasibility studies in a therapeutic beam, and summarizes the concepts towards the final large-scale assembly and readout system. Citation: Instruments PubDate: 2023-02-09 DOI: 10.3390/instruments7010009 Issue No:Vol. 7, No. 1 (2023)
Authors:Lucia Giuliano, Fabio Bosco, Martina Carillo, Giuseppe Felici, Luca Ficcadenti, Andrea Mostacci, Mauro Migliorati, Luigi Palumbo, Bruno Spataro, Luigi Faillace First page: 10 Abstract: In this paper, we illustrate the RF design and measurements of a C-band prototype structure for an Ultra High Dose Rate medical linac. (1) Background: FLASH Radiotherapy (RT) is a revolutionary new technique for cancer cure. It releases ultra-high radiation dose rates (above 100 Gy/s) in microsecond short pulses. In order to obtain a high dose in a very short time, accelerators with high-intensity currents (the order of 100 mA peak currents) have to be developed. In this contest, Sapienza University, in collaboration with SIT-Sordina IORT Technology spa, is developing a new C-band linac to achieve the FLASH regime. (2) Methods: We performed the RF electromagnetic design of the prototype of the C band linac using CST STUDIO Suite Code and the RF low power RF test at Sapienza University of Rome. The measurements of the field in the cavity have been done with the bead-pull technique. (3) Results: This device is a nine-cell structure operating on the π/2 mode at 5.712 GHz (C-band). We report and discuss the test measurement results on a full-scale copper prototype, showing good agreement with CST RF simulations. A tuning procedure has been implemented in order to ensure proper operating frequency and to reach a field profile flatness of the order of a few percent. (4) Conclusions: The prototype of a C-band linac for FLASH applications was successfully tested with low RF power at Sapienza University. The fabrication and ad hoc tuning procedures have been optimized and discussed in the paper. Citation: Instruments PubDate: 2023-02-22 DOI: 10.3390/instruments7010010 Issue No:Vol. 7, No. 1 (2023)
Authors:Suliman Alshammari, Abdullh Jabr, Saad Jaddua, Abdulhakim Alabadusalam First page: 11 Abstract: A compact microwave ECR ion source with low operating power was tested and commissioned for the ion injector line in the multipurpose low-energy ELASR storage ring facility at King Abdulaziz City for Science and Technology (KACST) in Riyadh. The compact ECR ion source can deliver singly charged ions with an energy of up to 50 keV and a beam current of up to 50 μA or up to 500 µA with a larger extraction aperture. The plasma in the ECR chamber is driven by a simple transmitter antenna, making the overall size of the ion source only 6 cm in diameter, which is relatively small when compared with other ECR systems. Additionally, the source operates without a high-voltage platform, which significantly reduces the overall footprint and simplifies the system operation. In this paper, the mechanical design and modeling of the ECR ion source are introduced, and the layout of the first part of the beam line is presented along with the numerical simulation results. In addition, the experimental results obtained for the first generated ion beam and commissioning of the ECR ion source are introduced and discussed. Citation: Instruments PubDate: 2023-02-23 DOI: 10.3390/instruments7010011 Issue No:Vol. 7, No. 1 (2023)
Authors:Wenping Guo, Yuan Huang, Chunhua Liu, Zhen Feng, Zhipei Hou, Wenyan Zhai, Hisamichi Funaba, Ichihiro Yamada, Yonggao Li, Zhongbin Shi First page: 12 Abstract: The Thomson scattering diagnostic of the HL-2A tokamak device was upgraded to improve its multi-point diagnostic capability, including new collection optics, fibers bundles, and data analysis code. The small old collection lens was replaced by a six-piece lens with a Cooke optical design. The aperture of its first standard sphere face is 310.125 mm, which successfully increases the amount of collected scattering light by about three times. The new collection optic module allows for up to twenty-six spatial points. A kind of Y-type fiber bundle has also been used to ensure that the fiber end-face matches the image of the laser beam exactly. Additionally, the new data analysis code can provide preview results in seconds. Finally, the multi-point Te diagnostic ability has been significantly improved. Citation: Instruments PubDate: 2023-03-06 DOI: 10.3390/instruments7010012 Issue No:Vol. 7, No. 1 (2023)
Authors:Sarah Barnes, Anzori Georgadze, Andrea Giammanco, Madis Kiisk, Vitaly A. Kudryavtsev, Maxime Lagrange, Olin Lyod Pinto First page: 13 Abstract: A key task for customs workers is the interception of hazardous, illegal and counterfeit items in order to protect the health and safety of citizens. However, it is estimated that only a small fraction of cargo is inspected and an even smaller fraction of trafficked goods are detected. Today, the most widely used technology for scanning vehicles, ranging from vans and trucks to railcars, is γ ray and X-ray radiography. New technologies are required to overcome current technological shortcomings, such as the inability to detect the target material composition, the usage of harmful ionising radiation sources and the resultant low throughput. Cosmic ray tomography (CRT) is a promising technology for cargo screening. Cosmic ray muons have average energies of around 10,000 times larger than a typical X-ray and therefore can penetrate relatively large and dense materials. By analysing muon scattering, it is possible to identify materials hidden inside shielding that is too thick or deep for other imaging methods. CRT is also completely passive, exploiting naturally occurring secondary cosmic radiation, and is therefore safe for humans and animals. Contrary to conventional X-ray- or γ-ray-based imaging techniques, CRT also allows material differentiation and anomaly localisation within the cargo or vehicle through the provision of 3D images. This article reviews the current state-of-the-art technology in CRT, critically assessing the strengths and weaknesses of the method, and suggesting further directions for development. Citation: Instruments PubDate: 2023-03-20 DOI: 10.3390/instruments7010013 Issue No:Vol. 7, No. 1 (2023)
Open Access journal
