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Sample records for array scintillation detector

  1. Performance Test of LASCAR Scintillator Detector Array at RIBLL

    Institute of Scientific and Technical Information of China (English)

    WangJinchuan; XiaoGuoqing; GuoZhongyan; ZhanWenlong; QiHuirong; WuLijie; XuZhiguo; ZhangLi; DingXianli; XuHushan; SunZhiyu; LiJiaxing; LiChen; WangMeng; ChenLixin; HuZhengguo; MaoRuishi; ZhaoTiecheng

    2003-01-01

    The LASCAR (Large Area Scattering Chamber at PABLL) scintillator detector array is developed to detect neutrons and charged particles from the reaction induced by, the RIBs from RIBLL. It consists of 8 scintillator plus light guide blocks. As shown in Fig.l, each block matches with 49 photomultipliers (PMTs) of 9214SB type from Electron Tubes Limited. Some technical improvements and the latest performance test of the 294 PMTs in 6 blocks of LASCAR are described in this report.

  2. Large Area Scintillator Fiber Ion Detector Array Used in Vacuum

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The large area plastic scintillator fiber(BCF-12)ion detector array is mainly made of 4×108 fibers,2×108 photo-transmitters and 2×108 photomultiplier tubes.The fiber with single clad is about 111cm long and its cross seetion is a square whose size is 5 mm×5 mm.The fibers are arrayed perpendicularly to the direction of the incident beam.Each end side of every four pieces of fiber is connected to a bended photo-transmitter

  3. Monte Carlo simulation of the standardization of {sup 22}Na using scintillation detector arrays

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Y., E-mail: yss.sato@aist.go.j [National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, Quantum Radiation Division, Radioactivity and Neutron Section, Tsukuba Central 2, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan); Murayama, H. [National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage, Chiba 263-8555 (Japan); Yamada, T. [Japan Radioisotope Association, 2-28-45, Hon-komagome, Bunkyo, Tokyo 113-8941 (Japan); National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, Quantum Radiation Division, Radioactivity and Neutron Section, Tsukuba Central 2, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan); Tohoku University, 6-6, Aoba, Aramaki, Aoba, Sendai 980-8579 (Japan); Hasegawa, T. [Kitasato University, 1-15-1, Kitasato, Sagamihara, Kanagawa 228-8555 (Japan); Oda, K. [Tokyo Metropolitan Institute of Gerontology, 1-1 Nakacho, Itabashi-ku, Tokyo 173-0022 (Japan); Unno, Y.; Yunoki, A. [National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, Quantum Radiation Division, Radioactivity and Neutron Section, Tsukuba Central 2, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan)

    2010-07-15

    In order to calibrate PET devices by a sealed point source, we contrived an absolute activity measurement method for the sealed point source using scintillation detector arrays. This new method was verified by EGS5 Monte Carlo simulation.

  4. Gamma-ray imaging detectors based on silicon drift detectors arrays coupled to a single scintillator

    International Nuclear Information System (INIS)

    Arrays of Silicon Drift Detectors (SDDs) coupled to a single scintillator, according to the Anger Camera scheme, can be successfully employed in gamma-ray imaging. The low value of output capacitance of a SDD allows to reach a lower electronics noise with respect to conventional silicon photodiodes used in scintillation detection. A small prototype of gamma camera with sub-millimeter resolution has been realized by using a monolithic array of small SDDs (5 mm2 each unit) with on-chip JFET. For the realization of gamma cameras of larger areas based on single units assembled in array, SDDs of 30 mm2 of area with external JFET have been also experimented

  5. Mass Composition Sensitivity of an Array of Water Cherenkov and Scintillation Detectors

    CERN Document Server

    Gonzalez, Javier G; Roth, Markus

    2011-01-01

    We consider a hybrid array composed of scintillation and water Cherenkov detectors designed to measure the cosmic ray primary mass composition at energies of about 1 EeV. We have developed a simulation and reconstruction chain to study the theoretical performance of such an array. In this work we investigate the sensitivity of mass composition observables in relation to the geometry of the array. The detectors are arranged in a triangular grid with fixed 750 m spacing and the configuration of the scintillator detectors is optimized for mass composition sensitivity. We show that the performance for composition determination can be compared favorably to that of Xmax measurements after the difference in duty cycles is considered.

  6. Image quality evaluation of linear plastic scintillating fiber array detector for X-ray imaging

    Institute of Scientific and Technical Information of China (English)

    Mohammad Mehdi NASSERI; MA Qing-Li; YIN Ze-Jie

    2004-01-01

    It is important to assess image quality, in order to ensure that the imaging system is performing optimally and also identify the weak points in an imaging system. Three parameters mostly leading to image degradation are contrast, spatial resolution and noise. There is always a trade-off between spatial resolution and signal to noise ratio,but in scintillating fiber array detectors spatial resolution is not as important as signal to noise ratio, so we paid more attention to contrast and SNR of the system. By using GEANT4 Monte Carlo detector simulation toolkit, some effective parameters of the linear plastic scintillating fiber (PSF) array as an imaging detector were investigated. Finally we show that it is possible to use this kind of detector to take CT and DR (Digital Radiography) image under certain conditions.

  7. The development of a single-crystal fiber-array scintillator area detector

    International Nuclear Information System (INIS)

    The scientific output of a neutron instrument is directly proportional to the effectiveness of its detector system-coverage of scattering area, pixel resolution, counting efficiency, signal-to-noise ratio, life time and cost. The current neutron scintillator detectors employ mainly 6Li-doped glass and ZnS, both of which present well-know limitations such as low light output, high gamma sensitivity in the case of 6Li-glass and optical opacity in the case of ZnS. We aim to develop a position-sensitive, flight-time differentiable, efficient and cost-effective neutron detector system based on single-crystal scintillator fiber-arrays. The laser-heated melt modulation fiber growth technology developed at NASA provides the means to grow high-purity single-crystal fibers or rods of variable diameters (200 μm to 5 mm) and essentially unlimited length. Arrays of such fibers can be tailored to meet the requirements of pixel size, geometric configuration, and coverage area for a detector system. We report a plan in the growth and characterization of scintillators based on lithium silicates and boron aluminates using Ce as activator. (author)

  8. Development of the Plastic Scintillator Detector Array for the Prototype of the Dark Matter Particle Explorer

    Science.gov (United States)

    Zhang, Yongjie; Sun, Zhiyu; Yu, Yuhong; Zhou, Yong; Fang, Fang; Chen, Junling

    2016-07-01

    The scientific object of Dark Matter Particles Explorer(DAMPE) is the measurement of electrons and photons in the range of 5GeV~10TeV and the flux of nuclei up to 500TeV with excellent resolution , and the realization of measurements will identify possible Dark Matter(DM) signature and help deepen our understanding of the origin and propagation of high energy cosmic ray respectively. Plastic Scintillator Detector Array (PSD), which adopts perpendicular structure with two layers and each layer consists of 15 scintillator strips, is one sub-detector of DAMPE for detecting heavy ions and distinguishing photons and electrons. In this paper, the design and some test results of PSD are to be described.

  9. Assessment of array scintillation detector for follicle thyroid 2-D image acquisition using Monte Carlo simulation

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Carlos Borges da; Santanna, Claudio Reis de [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)]. E-mails: borges@ien.gov.br; santanna@ien.gov.br; Braz, Delson [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Lab. de Instrumentacao Nuclear]. E-mail: delson@lin.ufrj.br; Carvalho, Denise Pires de [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Biofisica Carlos Chagas Filho. Lab. de Fisiologia Endocrina]. E-mail: dencarv@ufrj.br

    2007-07-01

    This work presents an innovative study to find out the adequate scintillation inorganic detector array to be used coupled to a specific light photo sensor, a charge coupled device (CCD), through a fiber optic plate. The goal is to choose the type of detector that fits a 2-dimensional imaging acquisition of a cell thyroid tissue application with high resolution and detection efficiency in order to map a follicle image using gamma radiation emission. A point or volumetric source - detector simulation by using a MCNP4B general code, considering different source energies, detector materials and geometry including pixel sizes and reflector types was performed. In this study, simulations were performed for 7 x 7 and 127 x 127 arrays using CsI(Tl) and BGO scintillation crystals with pixel size ranging from 1 x 1 cm{sup 2} to 10 x 10 {mu}m{sup 2} and radiation thickness ranging from 1 mm to 10 mm. The effect of all these parameters was investigated to find the best source-detector system that result in an image with the best contrast details. The results showed that it is possible to design a specific imaging system that allows searching for in-vitro studies, specifically in radiobiology applied to endocrine physiology. (author)

  10. Characterization of array scintillation detector for follicle thyroid 2D imaging acquisition using Monte Carlo simulation

    International Nuclear Information System (INIS)

    The image acquisition methods applied to nuclear medicine and radiobiology are a valuable research study for determination of thyroid anatomy to seek disorders associated to follicular cells. The Monte Carlo (MC) simulation has also been used in problems related to radiation detection in order to map medical images since the improvement of data processing compatible with personnel computers (PC). This work presents an innovative study to find out the adequate scintillation inorganic detector array that could be coupled to a specific light photo sensor, a charge coupled device (CCD) through a fiber optic plate in order to map the follicles of thyroid gland. The goal is to choose the type of detector that fits the application suggested here with spatial resolution of 10 μm and good detector efficiency. The methodology results are useful to map a follicle image using gamma radiation emission. A source - detector simulation is performed by using a MCNP4B (Monte Carlo for Neutron Photon transport) general code considering different source energies, detector materials and geometries including pixel sizes and reflector types. The results demonstrate that by using MCNP4B code is possible to searching for useful parameters related to the systems used in nuclear medicine, specifically in radiobiology applied to endocrine physiology studies to acquiring thyroid follicles images. (author)

  11. Dosimetric performance and array assessment of plastic scintillation detectors for stereotactic radiosurgery quality assurance

    International Nuclear Information System (INIS)

    Purpose: To compare the performance of plastic scintillation detectors (PSD) for quality assurance (QA) in stereotactic radiosurgery conditions to a microion-chamber (IC), Gafchromic EBT2 films, 60 008 shielded photon diode (SD) and unshielded diodes (UD), and assess a new 2D crosshair array prototype adapted to small field dosimetry. Methods: The PSD consists of a 1 mm diameter by 1 mm long scintillating fiber (BCF-60, Saint-Gobain, Inc.) coupled to a polymethyl-methacrylate optical fiber (Eska premier, Mitsubishi Rayon Co., Ltd., Tokyo, Japan). Output factors (Sc,p) for apertures used in radiosurgery ranging from 4 to 40 mm in diameter have been measured. The PSD crosshair array (PSDCA) is a water equivalent device made up of 49 PSDs contained in a 1.63 cm radius area. Dose profiles measurements were taken for radiosurgery fields using the PSDCA and were compared to other dosimeters. Moreover, a typical stereotactic radiosurgery treatment using four noncoplanar arcs was delivered on a spherical phantom in which UD, IC, or PSD was placed. Using the Xknife planning system (Integra Radionics Burlington, MA), 15 Gy was prescribed at the isocenter, where each detector was positioned. Results: Output Factors measured by the PSD have a mean difference of 1.3% with Gafchromic EBT2 when normalized to a 10 x 10 cm2 field, and 1.0% when compared with UD measurements normalized to the 35 mm diameter cone. Dose profiles taken with the PSD crosshair array agreed with other single detectors dose profiles in spite of the presence of the 49 PSDs. Gamma values comparing 1D dose profiles obtained with PSD crosshair array with Gafchromic EBT2 and UD measured profiles shows 98.3% and 100.0%, respectively, of detector passing the gamma acceptance criteria of 0.3 mm and 2%. The dose measured by the PSD for a complete stereotactic radiosurgery treatment is comparable to the planned dose corrected for its SD-based Sc,p within 1.4% and 0.7% for 5 and 35 mm diameter cone, respectively

  12. Study on the energy response to neutrons for a new scintillating-fiber-array neutron detector

    CERN Document Server

    Zhang Qi; Wang Qun; Xie Zhong Shen

    2003-01-01

    The energy response of a new scintillating-fiber-array neutron detector to neutrons in the energy range 0.01 MeV<=E sub n<=14 MeV was modeled by combining a simplified Monte Carlo model and the MCNP 4b code. In order to test the model and get the absolute sensitivity of the detector to neutrons, one experiment was carried out for 2.5 and 14 MeV neutrons from T(p,n) sup 3 He and T(d,n) sup 4 He reactions at the Neutron Generator Laboratory at the Institute of Modern Physics, the Chinese Academy of Science. The absolute neutron fluence was obtained with a relative standard uncertainty 4.5% or 2.0% by monitoring the associated protons or sup 4 He particles, respectively. Another experiment was carried out for 0.5, 1.0, 1.5, 2.0, 2.5 MeV neutrons from T(p,n) sup 3 He reaction, and for 3.28, 3.50, 4.83, 5.74 MeV neutrons from D(d,n) sup 3 He reaction on the Model 5SDH-2 accelerator at China Institute of Atomic Energy. The absolute neutron fluence was obtained with a relative standard uncertainty 5.0% by usin...

  13. Development of an application specific scintimammography detector based on a crystal scintillator array and a PSPMT

    CERN Document Server

    Majewski, S; Goode, A; Kross, B J; Steinbach, D; Weisenberger, A; Williams, M; Wojci, R

    1998-01-01

    We report the results of studies conducted with small field of view scintimammography camera based on a position-sensitive photomultiplier tube (5'' Hamamatsu R3292) and several pixelized crystal scintillator arrays made of YAP, CsI(Na) and NaI(Tl) scintillators. Laboratory tests and pre-clinical phantom studies were conducted to compare and optimize the performances of the prototypes with special emphasis on spatial resolution (approx 2-3mm) and sufficient energy resolution for scatter rejection.

  14. Extruded Plastic Scintillation Detectors

    CERN Document Server

    Pla-Dalmau, A; Mellott, K L; Pla-Dalmau, Anna; Bross, Alan D.; Mellott, Kerry L.

    1999-01-01

    As a way to lower the cost of plastic scintillation detectors, commercially available polystyrene pellets have been used in the production of scintillating materials that can be extruded into different profiles. The selection of raw materials is discussed. Two techniques to add wavelength shifting dopants to polystyrene pellets and to extrude plastic scintillating strips are described. Data on light yield and transmittance measurements are presented.

  15. Microfluidic Scintillation Detectors

    CERN Multimedia

    Microfluidic scintillation detectors are devices of recent introduction for the detection of high energy particles, developed within the EP-DT group at CERN. Most of the interest for such technology comes from the use of liquid scintillators, which entails the possibility of changing the active material in the detector, leading to an increased radiation resistance. This feature, together with the high spatial resolution and low thickness deriving from the microfabrication techniques used to manufacture such devices, is desirable not only in instrumentation for high energy physics experiments but also in medical detectors such as beam monitors for hadron therapy.

  16. Design of Multi-unit Control System of High Voltage Power Supply for LASCAR Scintillator Detector Array

    Institute of Scientific and Technical Information of China (English)

    WuLijie; WangJinchuan; XiaoGuoqing; GuoZhongyan; ZhanWenlong; QiHuirong; XuZhiguo; ZhangLi; DingXianli; XuHushan; SunZhiyu; LiJiaxing; LiChen; WangMeng; ChenLixin; HuZhengguo; MaoRuishi; ZhaoTiecheng

    2003-01-01

    The power voltages of Photomultipliers (PMTs) at RIBLL LASCAR scintillator detector array are distributed between 900 V and 1 800 V irregularly. 392 CC123 modules are employed to supply high voltage for the PMT array. The CC123 module serves as PMT interface groupware package, and it can transform +12 V DC input voltage to ranges of 0~-2200 V for the PMT power supply corresponding to 0~+5 V output voltage from the control board crate. The relation of PMT power supply with the output voltage of the control crate is shown in Fig.1.

  17. A high-spatial-resolution three-dimensional detector array for 30-200 keV X-rays based on structured scintillators

    DEFF Research Database (Denmark)

    Olsen, Ulrik Lund; Schmidt, Søren; Poulsen, Henning Friis

    2008-01-01

    A three-dimensional X-ray detector for imaging 30-200 keV photons is described. It comprises a set of semi-transparent structured scintillators, where each scintillator is a regular array of waveguides in silicon, and with pores filled with CsI. The performance of the detector is described theore...... efficiency by a factor of 5-15 is obtainable. The cross-talk between screens in the three-dimensional detector is shown to be negligible. The three-dimensional concept enables ray-tracing and super-resolution algorithms to be applied.......A three-dimensional X-ray detector for imaging 30-200 keV photons is described. It comprises a set of semi-transparent structured scintillators, where each scintillator is a regular array of waveguides in silicon, and with pores filled with CsI. The performance of the detector is described...

  18. Wafer-scale pixelated scintillator and specially designed data acquisition system for fiber optic taper array-coupled digital x-ray detector

    International Nuclear Information System (INIS)

    A digital x-ray detector scheme based on a pixelated scintillator coupled with a fiber optic (FOT) array is suitable for many high-resolution x-ray imaging applications. However, certain challenges need to be addressed for fabrication of wafer-scale uniform pixelated x-ray scintillators. In addition, difficulties associated with implementation of the data acquisition system for acquiring output image data from the multiple image sensors used in the detector also need to be addressed. In this paper, a 2×2 FOT array-coupled digital x-ray detector scheme using a 5-in. pixelated scintillator is proposed. A novel fabrication setup along with the corresponding processes for fabricating the wafer-scale pixelated scintillator and implementation of a specially designed embedded data acquisition system based on a single embedded micro-processer (ARM) and four field-programmable gate array (FPGA) chips are discussed in detail. Preliminary experiments demonstrate that this pixelated scintillator-based digital x-ray detector scheme with an active imaging area of about 100 mm×100 mm shows considerable potential for use in high-resolution x-ray imaging

  19. Wafer-scale pixelated scintillator and specially designed data acquisition system for fiber optic taper array-coupled digital x-ray detector

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Zhigang; Li, Ji; Lei, Yaohu; Wang, Ru; Ren, Jianping; Qiao, Jian; Niu, Hanben, E-mail: szuoptoelectronics@163.com

    2015-09-21

    A digital x-ray detector scheme based on a pixelated scintillator coupled with a fiber optic (FOT) array is suitable for many high-resolution x-ray imaging applications. However, certain challenges need to be addressed for fabrication of wafer-scale uniform pixelated x-ray scintillators. In addition, difficulties associated with implementation of the data acquisition system for acquiring output image data from the multiple image sensors used in the detector also need to be addressed. In this paper, a 2×2 FOT array-coupled digital x-ray detector scheme using a 5-in. pixelated scintillator is proposed. A novel fabrication setup along with the corresponding processes for fabricating the wafer-scale pixelated scintillator and implementation of a specially designed embedded data acquisition system based on a single embedded micro-processer (ARM) and four field-programmable gate array (FPGA) chips are discussed in detail. Preliminary experiments demonstrate that this pixelated scintillator-based digital x-ray detector scheme with an active imaging area of about 100 mm×100 mm shows considerable potential for use in high-resolution x-ray imaging.

  20. Scintillating fiber detector

    CERN Document Server

    Vozak, Matous

    2016-01-01

    NA61 is one of the physics experiments at CERN dedicated to study hadron states coming from interactions of SPS beams with various targets. To determine the position of a secondary beam, three proportional chambers are placed along the beamline. However, these chambers tend to have slow response. In order to obtain more precise time information, use of another detector is being considered. Fast response and compact size is making scintillation fiber (SciFi) with silicon photomultiplier (Si-PM) read out a good candidate. This report is focused on analysing data from SciFi collected in a test beam at the beginning of July 2016.

  1. Scintillation detectors of Alborz-I experiment

    International Nuclear Information System (INIS)

    A new air shower experiment of the Alborz Observatory, Alborz-I, located at the Sharif University of Technology, Iran, will be constructed in near future. An area of about 30×40 m2 will be covered by 20 plastic scintillation detectors (each with an area of 50×50 cm2). A series of experiments have been performed to optimize the height of light enclosures of the detectors for this array and the results have been compared to an extended code simulation of these detectors. Operational parameters of the detector obtained by this code are cross checked by the Geant4 simulation. There is a good agreement between the extended-code and Geant4 simulations. We also present further discussions on the detector characteristics, which can be applicable for all scintillation detectors with a similar configuration

  2. Scintillation detectors of Alborz-I experiment

    CERN Document Server

    Pezeshkian, Yousef; Motlagh, Mehdi Abbasian; Rezaie, Masoume

    2014-01-01

    A new air shower experiment of the Alborz Observatory, Alborz-I, located at the Sharif University of Technology, Iran, will be constructed in near future. An area of about 30$\\times$40 m$^{2}$ will be covered by 20 plastic scintillation detectors (each with an area of 50$\\times$50 cm$^{2}$). A series of experiments have been performed to optimize the height of light enclosures of the detectors for this array and the results have been compared to an extended code simulation of these detectors. Operational parameters of the detector obtained by this code are cross checked by Geant4 simulation. There is a good agreement between extended-code and Geant4 simulations. We also present further discussions on the detector characteristics, which can be applicable for all scintillation detectors with a similar configuration.

  3. Simulation on spatial resolution of scintillator arrays based on neutron penumbral imaging system

    International Nuclear Information System (INIS)

    In order to compare three kinds of scintillation detectors, the Monte Carlo method is introduced to calculate the spatial resolution and energy deposition of scintillator arrays with different fiber diameters. According to simulation results, the resolution of standard liquid scintillator array is better than that of plastic scintillator array, and the resolution of deuterated liquid scintillator array is almost half that of standard liquid scintillator array. The energy deposition of hydrogen-rich scintillator is higher than that of deuterated scintillator. Moreover, smaller fiber diameter leads to better spatial resolution, and thicker scintillator leads to higher energy deposition. (authors)

  4. Homestake scintillation detectors. A status report

    Energy Technology Data Exchange (ETDEWEB)

    Cherry, M.L.; Corbato, S.; Daily, T.; Kieda, D.; Lande, K.; Lee, C.K.

    We describe the 140 ton, 1200 m/sup 2/ sr Large-Area Scintillation Detector located underground at a depth of 4850 ft and the 0.8 km/sup 2/ surface air shower array at the Homestake Mine. Half of the underground detector is currently operating. We discuss its performance and describe the monopole sensitivity of the LASD and the ability of the surface-underground telescope to detect cosmic point sources.

  5. Scintillators and other particle optical detectors

    International Nuclear Information System (INIS)

    The author reports and comments his researcher career in the field of particle optical detectors. He addresses the cases of organic scintillators (scintillating fibers, liquid scintillators), inorganic scintillators (crystals for electromagnetic calorimetry, crystals for solar neutrino spectroscopy), and Cherenkov Effect detectors. He also reports his works on Cd Te detectors and their modelling

  6. The DEuterated SCintillator Array for Neutron Tagging

    Directory of Open Access Journals (Sweden)

    Wong J.

    2014-03-01

    Full Text Available A neutron tagging array based upon liquid deuterated scintillators is being developed for the study of neutron-rich systems. The DEuterated SCintillator Array for Neutron Tagging, or DESCANT, will serve as an auxiliary detector for both the TIGRESS and GRIFFIN γ-ray spectrometers located at TRIUMF’s ISAC radioactive ion beam facility. DESCANT is comprised of 70 pseudohexaconical detectors of five varieties. The array is fully close-packed, subtends a downstream angle of θ = 65° and covers 92.6% of this solid angle or 1.08π sr. Each detector is 150 mm thick and filled with Bicron BC-537 liquid deuterated scintillator. The white, red and blue detectors are viewed by 127 mm diameter Hamamatsu R4155 photomultiplier tubes while the yellow and green detectors are viewed by 78 mm diameter ET Enterprises 9822B photomultiplier tubes. The aim of this work is to report on the mechanical design of DESCANT and the performance of a prototype detector measured using mono-energetic neutrons.

  7. Validated simulation for LYSO:Ce scintillator based PET detector modules built on fully digital SiPM arrays

    International Nuclear Information System (INIS)

    In the recent years new digital photon counter devices (also known as silicon photomultipliers, SiPMs) were designed and manufactured to be used specifically in positron emission tomography (PET) scanners. These finely pixelated devices opened new opportunities in PET detector development, hence their application with monolithic scintillator crystals now are of particular interest. We worked out a simulation tool and a corresponding validation method to assist the optimization and characterization of such PET detector modules. During our work we concentrated on the simulation of SPADnet sensors and the LYSO:Ce scintillator material. Validation of our algorithms combines measurements and simulations performed on UV-excited detector modules. In this paper we describe the operation of the simulation method in detail and present the validation scheme for two demonstrative PET detector-like modules: one built of a scintillator with black-painted faces and another with polished faces. By evaluating the results we show that the shape deviation of the average light distributions is lower than 13%, and the pixel count statistics follow Poisson distribution for both measurement and simulation. The calculated total count values have less than 10% deviation from the measured ones

  8. Position determination in scintillation detectors

    International Nuclear Information System (INIS)

    Three different methods are described to determine the ''true'' positions of a scintillation event in one- and two-dimensional position-sensitive scintillation detectors from experimental calibration data. Under certain assumptions the methods are shown to yield mathematically exact results. Computer-simulated results are presented to demonstrate the validity of the methods, to estimate the consequence of approximations to be made, and to provide figures for the required accuracy of experimental data. Results concerning spatial resolution and linearity of the response are discussed for the case that scintillation events are stored according to the precalculated and tabulated ''true'' positions. (orig.)

  9. Characterization of liquid scintillation detectors

    CERN Document Server

    Schmidt, D; Böttger, R; Klein, H; Lebreton, L; Neumann, S; Nolte, R; Pichenot, G

    2002-01-01

    Five scintillation detectors of different scintillator size and type were characterized. The pulse height scale was calibrated in terms of electron light output units using photon sources. The response functions for time-of-flight (TOF)-selected monoenergetic neutrons were experimentally determined and also simulated with the NRESP code over a wide energy range. A comparison of the measured and calculated response functions allows individual characteristics of the detectors to be determined and the response matrix to be reliably derived. Various applications are discussed.

  10. Novel radiation hard microfabricated scintillation detectors with high spatial resolution

    CERN Document Server

    Mapelli, A; Haguenauerc, M; Jiguet, S; Vico Triviño, N; Renaud, P

    2010-01-01

    A novel liquid scintillation detector with high spatial resolution is being developed with standard microfabrication techniques. It consists of a dense array of scintillating waveguides obtained by filling microfluidic channels with an organic liquid scintillator and optically coupled to a pixellated photodetector. Such a microfluidic device can be designed and processed to meet the requirements of a wide range of applications like medical imaging, homeland security and high-energy physics. High-spatial resolution miniaturized detectors as well as large-area detectors can easily be fabricated. The fabrication process of a prototype detector and experimental results are presented in this paper.

  11. ScintSim1: A new Monte Carlo simulation code for transport of optical photons in 2D arrays of scintillation detectors

    OpenAIRE

    Mosleh-Shirazi, Mohammad Amin; Zarrini-Monfared, Zinat; Karbasi, Sareh; Zamani, Ali

    2014-01-01

    Two-dimensional (2D) arrays of thick segmented scintillators are of interest as X-ray detectors for both 2D and 3D image-guided radiotherapy (IGRT). Their detection process involves ionizing radiation energy deposition followed by production and transport of optical photons. Only a very limited number of optical Monte Carlo simulation models exist, which has limited the number of modeling studies that have considered both stages of the detection process. We present ScintSim1, an in-house opti...

  12. A remote reactor monitoring with plastic scintillation detector

    CERN Document Server

    Georgadze, A Sh; Ponkratenko, O A; Litvinov, D A

    2016-01-01

    Conceiving the possibility of using plastic scintillator bars as robust detectors for antineutrino detection for the remote reactor monitoring and nuclear safeguard application we study expected basic performance by Monte Carlo simulation. We present preliminary results for a 1 m3 highly segmented detector made of 100 rectangular scintillation bars forming an array which is sandwiched at both sides by the continuous light guides enabling light sharing between all photo detectors. Light detection efficiency is calculated for several light collection configurations, considering different scintillation block geometries and number of photo-detectors. The photo-detectors signals are forming the specific hit pattern, which is characterizing the impinging particle. The statistical analysis of hit patterns allows effectively select antineutrino events and rejects backgrounds. To evaluate detector sensitivity to fuel isotopic composition evolution during fuel burning cycle we have calculated antineutrino spectra. The ...

  13. Characterization and testing of EJ-309 and Stilbene scintillation detectors

    Science.gov (United States)

    Baramsai, B.; Jandel, M.; Bredeweg, T. A.; Couture, A.; Mosby, S.; Rusev, G.; Ullmann, J. L.; Walker, C. L.

    2015-09-01

    A new neutron detector array (NEUANCE) is under development at the Los Alamos Neutron Science Center (LANSCE). After completion, NEUANCE will be installed in the central cavity of the 3.6π Υ-ray detector array DANCE located at the Lujan Center of LANSCE. The detector system, with simultaneous neutron and -ray detection capability, will be used to study neutron-induced capture and session reactions. The response of a EJ-309 scintillation detector to Υ-ray and neutron radiation was measured using the standard Υ-ray and 252Cf sources. The light from the detector was collected using a Hamamatsu photomultiplier tube or a Silicon photomultiplier GEANT4 was used to understand the light output and the optical photon transport in the scintillation. The detector geometry and optimum parameters for the data acquisition system were determined based on the test results and the simulations.

  14. Scintillation Detectors for Charged Particles and Photons

    CERN Document Server

    Lecoq, P

    2011-01-01

    Scintillation Detectors for Charged Particles and Photons in 'Charged Particle Detectors - Particle Detectors and Detector Systems', part of 'Landolt-Börnstein - Group I Elementary Particles, Nuclei and Atoms: Numerical Data and Functional Relationships in Science and Technology, Volume 21B1: Detectors for Particles and Radiation. Part 1: Principles and Methods'. This document is part of Part 1 'Principles and Methods' of Subvolume B 'Detectors for Particles and Radiation' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the Subsection '3.1.1 Scintillation Detectors for Charged Particles and Photons' of Section '3.1 Charged Particle Detectors' of Chapter '3 Particle Detectors and Detector Systems' with the content: 3.1.1 Scintillation Detectors for Charged Particles and Photons 3.1.1.1 Basic detector principles and scintillator requirements 3.1.1.1.1 Interaction of ionizing radiation with scintillator material 3.1.1.1.2 Important scint...

  15. Homestake Large Area Scintillation Detector and cosmic ray telescope

    Energy Technology Data Exchange (ETDEWEB)

    Cherry, M.L.; Corbato, S.; Kieda, D.; Lande, K.; Lee, C.K.; Steinberg, R.I.

    1985-01-25

    The Homestake Large Area Scintillation Detector consists of 140 tons of liquid scintillator in a hollow 8 m x 8 m x 16 m box surrounding the Brookhaven /sup 37/Cl solar neutrino detector. The experiment is located at a depth of 4850 ft. (4200 m.w.e.) in the Homestake Gold Mine. Half of the detector is currently running; the full detector will be taking data early in 1985. An extensive air shower array is also currently under construction on the earth's surface above the underground chamber, consisting of 100 scintillators, each 3 m/sup 2/, covering approximately 0.8 km/sup 2/; the first portion of the surface array will also be providing data in early 1985. Together, the new Homestake detectors (Fig. 1) will be used to search for slow, massive magnetic monopoles; study the zenith angle distribution of neutrino-induced muons; search for neutrino bursts from the gravitational collapse of massive stars; measure the multiplicity and transverse momentum distributions of cosmic ray muons; and study the composition of the primary cosmic rays. In this paper, we present a progress report on the new detectors. In Sec. I we describe the underground device and its capabilities as a monopole detector; in Sec. II we describe the surface array and the cosmic ray studies; the neutrino measurements have been discussed elsewhere.

  16. Homestake Large Area Scintillation Detector and cosmic ray telescope

    International Nuclear Information System (INIS)

    The Homestake Large Area Scintillation Detector consists of 140 tons of liquid scintillator in a hollow 8 m x 8 m x 16 m box surrounding the Brookhaven 37Cl solar neutrino detector. The experiment is located at a depth of 4850 ft. (4200 m.w.e.) in the Homestake Gold Mine. Half of the detector is currently running; the full detector will be taking data early in 1985. An extensive air shower array is also currently under construction on the earth's surface above the underground chamber, consisting of 100 scintillators, each 3 m2, covering approximately 0.8 km2; the first portion of the surface array will also be providing data in early 1985. Together, the new Homestake detectors (Fig. 1) will be used to search for slow, massive magnetic monopoles; study the zenith angle distribution of neutrino-induced muons; search for neutrino bursts from the gravitational collapse of massive stars; measure the multiplicity and transverse momentum distributions of cosmic ray muons; and study the composition of the primary cosmic rays. In this paper, we present a progress report on the new detectors. In Sec. I we describe the underground device and its capabilities as a monopole detector; in Sec. II we describe the surface array and the cosmic ray studies; the neutrino measurements have been discussed elsewhere

  17. Glasses as active and passive components for scintillating fiber detectors

    International Nuclear Information System (INIS)

    Scintillating fibers are of growing interest in high energy physics for applications in calorimetry and in tracking detectors. At present plastic scintillating fibers are mainly used in these applications because of their high light yield and their fast decay rates; however, in thin fibers, required for high spatial resolution, these suffer from low attenuation lengths. Moreover, cross-talk is still a severe problem. As alternatives the authors will discuss the following two concepts: (1) using Ce- and Tb-doped multicomponent glasses as active core material of glass fibers and (2) using liquid scintillator filled glass capillary arrays. The optical properties of the rare earth doped glasses are described and the scintillation efficiency of the fibers and fiber bundles utilizing these glasses as core material are presented. Broad applications appear to be possible with liquid scintillator filled capillary arrays. Suitable liquid scintillators with high refractive index solvents and locally emitting solutes with high yields, short decay times and large Stokes-shifts are available. Arrays can be produced with and without extra mural absorber in various sizes and shapes. Theoretical estimates show that reflection losses at the liquid/glass interface do not effect the overall transmission up to length/diameter ratios of 105. In addition recent results have shown that the system resists radiation doses in the 100 kGy range. Further experimental results obtained at CERN with these arrays will be discussed

  18. Detectors for proton counting. Si-APD and scintillation detectors

    International Nuclear Information System (INIS)

    Increased intensity of synchrotron radiation requests users to prepare photon pulse detectors having higher counting rates. As detectors for photon counting, silicon-avalanche photodiode (Si-APD) and scintillation detectors were chosen for the fifth series of detectors. Principle of photon detection by pulse and need of amplification function of the detector were described. Structure and working principle, high counting rate measurement system, bunch of electrons vs. counting rate, application example of NMR time spectroscopy measurement and comments for users were described for the Si-APD detector. Structure of scintillator and photomultiplier tube, characteristics of scintillator and performance of detector were shown for the NaI detector. Future development of photon pulse detectors was discussed. (T. Tanaka)

  19. Constant fraction timing with scintillation detectors

    International Nuclear Information System (INIS)

    A model is presented for constant fraction pick-off timing with scintillator-photomultiplier detectors based on a statistical method for leading edge timing. Many of the essential features of this technique are obtained such as prompt time-response, the dependence of FWHM on dynamic range of pulse heights and on maximum energy deposited in scintillator; also the effect of delay time on the optimum resolution in CFPHT and ARC timing. The Walk component in this technique is also satisfactory reproduced

  20. Microfluidic Scintillation Detectors for High Energy Physics

    CERN Document Server

    Maoddi, Pietro; Mapelli, Alessandro

    This thesis deals with the development and study of microfluidic scintillation detectors, a technology of recent introduction for the detection of high energy particles. Most of the interest for such devices comes from the use of a liquid scintillator, which entails the possibility of changing the active material in the detector, leading to increased radiation resistance. A first part of the thesis focuses on the work performed in terms of design and modelling studies of novel prototype devices, hinting to new possibilities and applications. In this framework, the simulations performed to validate selected designs and the main technological choices made in view of their fabrication are addressed. The second part of this thesis deals with the microfabrication of several prototype devices. Two different materials were studied for the manufacturing of microfluidic scintillation detectors, namely the SU-8 photosensitive epoxy and monocrystalline silicon. For what concerns the former, an original fabrication appro...

  1. Scintillation detectors in computerized tomography

    Energy Technology Data Exchange (ETDEWEB)

    Gilar, O.; Pavlicek, Z.; Jursova, L. (Tesla, Premysleni (Czechoslovakia). Vyzkumny Ustav Pristroju Jaderne Techniky)

    1984-07-01

    A new scintillator, Bi/sub 4/Ge/sub 3/O/sub 12/ (BGO), was tested for use in the detection part of computerized tomographs. In comparison with the NaI(Tl) scintillator it has a three-fold mass stopping power and allows the detection of medium and high energy gamma radiation with a higher detection efficiency, i.e., for the same detection efficiency its size is much smaller. Some other mechanical, physical and optical parameters of the BGO scintillator are given. BGO is prospective for use in high energy spectrometry and may replace NaI(Tl) wherever the following parameters are significant: crystal size, detection efficiency for gamma radiation, and good spatial resolution.

  2. Semiconductor high-energy radiation scintillation detector

    Energy Technology Data Exchange (ETDEWEB)

    Kastalsky, A. [University at Stony Brook, ECE Department and NY State Center for Advanced Sensor Technology, Stony Brook, NY 11794-2350 (United States); Luryi, S. [University at Stony Brook, ECE Department and NY State Center for Advanced Sensor Technology, Stony Brook, NY 11794-2350 (United States)]. E-mail: serge.luryi@stonybrook.edu; Spivak, B. [Department of Physics, University of Washington, Seattle, WA 98195 (United States)

    2006-09-15

    We propose a new scintillation-type detector in which high-energy radiation generates electron-hole pairs in a direct-gap semiconductor material that subsequently recombine producing infrared light to be registered by a photo-detector. The key issue is how to make the semiconductor essentially transparent to its own infrared light, so that photons generated deep inside the semiconductor could reach its surface without tangible attenuation. We discuss two ways to accomplish this, one based on doping the semiconductor with shallow impurities of one polarity type, preferably donors, the other by heterostructure bandgap engineering. The proposed semiconductor scintillator combines the best properties of currently existing radiation detectors and can be used for both simple radiation monitoring, like a Geiger counter, and for high-resolution spectrography of the high-energy radiation. An important advantage of the proposed detector is its fast response time, about 1 ns, essentially limited only by the recombination time of minority carriers. Notably, the fast response comes without any degradation in brightness. When the scintillator is implemented in a qualified semiconductor material (such as InP or GaAs), the photo-detector and associated circuits can be epitaxially integrated on the scintillator slab and the structure can be stacked-up to achieve virtually any desired absorption capability.

  3. Study Performance of Liquid Scintillation Fiber Detector

    CERN Document Server

    Zhang, Yongpeng; Lu, Haoqi; Zhang, Peng; Zhang, Chengcai; Yang, Changgen

    2016-01-01

    Liquid scintillator (LS) with optical fiber detector (LSOF detector) is a new type of detector, which has been applied in large-scale particle physics experiments in recent years. We were proposing LSOF detector as one option of top veto detector in Jiangmen Underground Neutrino Observatory (JUNO) experiment. The prototype detector was located in laboratory of the institute of high energy physics (IHEP). From prototype study, we found that the detector have a good performance and can satisfy JUNO requirement. The detection efficiency of cosmic ray muon is greater than 98% and can collect 58 photon electrons (p.e.) when muon is going through the detector. Further more, the relationship between p.e., material reflectivity and LS depth are studied. We also compared the data with Monte Carlo simulation, and they have a good agreement with each other.

  4. Semiconductor High-Energy Radiation Scintillation Detector

    CERN Document Server

    Kastalsky, A; Spivak, B

    2006-01-01

    We propose a new scintillation-type detector in which high-energy radiation produces electron-hole pairs in a direct-gap semiconductor material that subsequently recombine producing infrared light to be registered by a photo-detector. The key issue is how to make the semiconductor essentially transparent to its own infrared light, so that photons generated deep inside the semiconductor could reach its surface without tangible attenuation. We discuss two ways to accomplish this, one based on doping the semiconductor with shallow impurities of one polarity type, preferably donors, the other by heterostructure bandgap engineering. The proposed semiconductor scintillator combines the best properties of currently existing radiation detectors and can be used for both simple radiation monitoring, like a Geiger counter, and for high-resolution spectrography of the high-energy radiation. The most important advantage of the proposed detector is its fast response time, about 1 ns, essentially limited only by the recombi...

  5. Maximum likelihood positioning and energy correction for scintillation detectors

    Science.gov (United States)

    Lerche, Christoph W.; Salomon, André; Goldschmidt, Benjamin; Lodomez, Sarah; Weissler, Björn; Solf, Torsten

    2016-02-01

    An algorithm for determining the crystal pixel and the gamma ray energy with scintillation detectors for PET is presented. The algorithm uses Likelihood Maximisation (ML) and therefore is inherently robust to missing data caused by defect or paralysed photo detector pixels. We tested the algorithm on a highly integrated MRI compatible small animal PET insert. The scintillation detector blocks of the PET gantry were built with the newly developed digital Silicon Photomultiplier (SiPM) technology from Philips Digital Photon Counting and LYSO pixel arrays with a pitch of 1 mm and length of 12 mm. Light sharing was used to readout the scintillation light from the 30× 30 scintillator pixel array with an 8× 8 SiPM array. For the performance evaluation of the proposed algorithm, we measured the scanner’s spatial resolution, energy resolution, singles and prompt count rate performance, and image noise. These values were compared to corresponding values obtained with Center of Gravity (CoG) based positioning methods for different scintillation light trigger thresholds and also for different energy windows. While all positioning algorithms showed similar spatial resolution, a clear advantage for the ML method was observed when comparing the PET scanner’s overall single and prompt detection efficiency, image noise, and energy resolution to the CoG based methods. Further, ML positioning reduces the dependence of image quality on scanner configuration parameters and was the only method that allowed achieving highest energy resolution, count rate performance and spatial resolution at the same time.

  6. Semiconductor High-Energy Radiation Scintillation Detector

    OpenAIRE

    Kastalsky, A.; Luryi, S.; Spivak, B

    2006-01-01

    We propose a new scintillation-type detector in which high-energy radiation produces electron-hole pairs in a direct-gap semiconductor material that subsequently recombine producing infrared light to be registered by a photo-detector. The key issue is how to make the semiconductor essentially transparent to its own infrared light, so that photons generated deep inside the semiconductor could reach its surface without tangible attenuation. We discuss two ways to accomplish this, one based on d...

  7. Characterization of the scintillation anisotropy in crystalline stilbene scintillator detectors

    CERN Document Server

    Schuster, Patricia

    2016-01-01

    This paper reports a series of measurements that characterize the directional dependence of the scintillation response of crystalline melt-grown and solution-grown stilbene to incident DT and DD neutrons. These measurements give the amplitude and pulse shape dependence on the proton recoil direction over one hemisphere of the crystal, confirming and extending previous results in the literature for melt-grown stilbene and providing the first measurements for solution-grown stilbene. In similar measurements of liquid and plastic detectors, no directional dependence was observed, confirming the hypothesis that the anisotropy in stilbene and other organic crystal scintillators is a result of internal effects due to the molecular or crystal structure and not an external effect on the measurement system.

  8. Development and studies of a novel microfabricated radiation hard scintillation particle detector with high spatial resolution

    CERN Document Server

    Mapelli, A; Haguenauer, M; Jiguet, S; Renaud, P

    2009-01-01

    A novel scintillation detector is being developed with standard microfabrication techniques. It consists of a dense array of scintillating waveguides obtained by filling microfluidic channels with an organic liquid scintillator. Such a microfluidic device can be designed and processed to meet the requirements of a wide range of applications like medical imaging, homeland security and high-energy physics. High-spatial resolution miniaturized detectors as well as large-area detectors can easily be fabricated. This paper presents the fabrication process of a prototype detector with 200 μm × 50 μm microchannels obtained by photolithography of the SU-8 photoresist. Preliminary experimental results are presented.

  9. Pulse-shape discrimination in NE213 liquid scintillator detectors

    Energy Technology Data Exchange (ETDEWEB)

    Cavallaro, M., E-mail: manuela.cavallaro@lns.infn.it [INFN-Laboratori Nazionali del Sud, Catania (Italy); CSFNSM, Catania (Italy); Tropea, S. [INFN-Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Fisica e Astronomia, Università di Catania, Catania (Italy); Agodi, C. [INFN-Laboratori Nazionali del Sud, Catania (Italy); Assié, M.; Azaiez, F. [Institut de Physique Nucléaire, Université Paris-Sud-11-CNRS/IN2P3, 91406 Orsay (France); Boiano, C. [INFN - Sezione di Milano, Milano (Italy); Bondì, M.; Cappuzzello, F.; Carbone, D. [INFN-Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Fisica e Astronomia, Università di Catania, Catania (Italy); De Napoli, M. [INFN - Sezione di Catania, Catania (Italy); Séréville, N. de [Institut de Physique Nucléaire, Université Paris-Sud-11-CNRS/IN2P3, 91406 Orsay (France); Foti, A. [Dipartimento di Fisica e Astronomia, Università di Catania, Catania (Italy); INFN - Sezione di Catania, Catania (Italy); Linares, R. [Instituto de Física da Universidade Federal Fluminense, Rio de Janeiro, Niterói, RJ (Brazil); Nicolosi, D. [INFN-Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Fisica e Astronomia, Università di Catania, Catania (Italy); Scarpaci, J.A. [Institut de Physique Nucléaire, Université Paris-Sud-11-CNRS/IN2P3, 91406 Orsay (France)

    2013-02-01

    The 16-channel fast stretcher BaFPro module, originally developed for processing signals of Barium Fluoride scintillators, has been modified to make a high performing analog pulse-shape analysis of signals from the NE213 liquid scintillators of the EDEN neutron detector array. The module produces two Gaussian signals, whose amplitudes are proportional to the height of the fast component of the output light and to the total energy deposited into the scintillator, respectively. An in-beam test has been performed at INFN-LNS (Italy) demonstrating a low detection threshold, a good pulse-shape discrimination even at low energies and a wide dynamic range for the measurement of the neutrons energy.

  10. The digitisation of the scintillating fibre detector

    CERN Document Server

    Cogneras, E; van Tilburg, J; de Vries, J

    2014-01-01

    In this note the digitisation of the scintillating fibre detector for the LHCb upgrade is described. The steps for transforming the hits generated by the GEANT simulation into a digital signal are given. The main effects of this detector are described in the simulation code for the LHCb upgrade. In particular, the attenuation of the fibres after irradiation, the geometry of the fibres with respect to the SiPM channels, the gain of the SiPM’s, the thermal noise, the noise from afterpulses and spillover, and the clustering are described. The output is given in the same data format as the one that is expected from the final detector.

  11. Development and Studies of Novel Microfabricated Radiation Hard Scintillation Detectors With High Spatial Resolution

    CERN Document Server

    Mapelli, A; Haguenauer, M; Jiguet, S; Renaud, P; Vico Triviño, N

    2011-01-01

    A new type of scintillation detector is being developed with standard microfabrication techniques. It consists of a dense array of scintillating waveguides obtained by coupling microfluidic channels filled with a liquid scintillator to photodetectors. Easy manipulation of liquid scintillators inside microfluidic devices allow their flushing, renewal, and exchange making the active medium intrinsically radiation hard. Prototype detectors have been fabricated by photostructuration of a radiation hard epoxy resin (SU-8) deposited on silicon wafers and coupled to a multi-anode photomultiplier tube (MAPMT) to read-out the scintillation light. They have been characterized by exciting the liquid scintillator in the 200 micrometers thick microchannels with electrons from a 90Sr yielding approximately 1 photoelectron per impinging Minimum Ionizing Particle (MIP). These promising results demonstrate the concept of microfluidic scintillating detection and are very encouraging for future developments.

  12. Current trends in scintillator detectors and materials

    CERN Document Server

    Moses, W W

    2002-01-01

    The last decade has seen a renaissance in inorganic scintillator development for gamma ray detection. Lead tungstate (PbWO sub 4) has been developed for high-energy physics experiments, and possesses exceptionally high density and radiation hardness, albeit with low luminous efficiency. Lutetium orthosilicate or LSO (Lu sub 2 SiO sub 5 :Ce) possesses a unique combination of high luminous efficiency, high density, and reasonably short decay time, and is now incorporated in commercial positron emission tomography cameras. There have been advances in understanding the fundamental mechanisms that limit energy resolution, and several recently discovered materials (such as LaBr sub 3 :Ce) possess energy resolution that approaches that of direct solid state detectors. Finally, there are indications that a neglected class of scintillator materials that exhibit near band-edge fluorescence could provide scintillators with sub-nanosecond decay times and high luminescent efficiency.

  13. Characterization of the lanthanum chloride scintillation detector

    International Nuclear Information System (INIS)

    This paper reports about the investigations on the performance of the new earth-rare halide Scintillator, the LaCl3:10%Ce, which has been discovered with attractive scintillation properties: fast, efficient, and high-energy resolution. The combination of good brightness and linear response has naturally resulted in a very good energy resolution, whereas the fast decay time promoted counting applications at very high rate and very fast timing resolution. Energy resolutions of (2.99±0.02) %, (8.66±0.02) %, and (2.05±0.01) % have been achieved by exciting the detector with 662 keV 137Cs, 122 keV 152Eu, and 1332.5 keV 60Co sources respectively, at room temperature. The variations of the resolution as a function of both shaping time and high voltage have been studied and found to be relatively linear. The timing resolution was also studied. The value of 1.07 ns FWHM has been recorded with LaCl3:10%Ce and BaF2 detectors operating in coincidence mode, using 1333.5 keV γ-ray 60Co peak. Compared to similar studies, this timing resolution was worse than expected even if the exciting radioactive sources used in the two experiments were different. The efficiency values of (0.24±0.01)%, (0.01±0.01)% and (0.09±0.01)% were obtained with laboratory 137Cs, 152Eu, 60Co isotopes respectively. These detector efficiency values were very low, due to the smaller detector sizes used in these earlier crystals and to the large detector-source-distance used in this experiment. The Lanthanum Chloride Scintillator detector is hygroscopic and relatively expensive compared to established scintillators. In addition, it carries internal contamination in 138La and 227Ac for larger thicknesses. Nevertheless, the energy resolution figures achieved, twice as good as that of NaI(Tl), are in good agreement with those reported elsewhere. They credit the scintillation detectors as good challengers of semiconductor-based detectors, allowing their application fields to be extended. (author)

  14. Monopole search and neutrino astrophysics with liquid scintillation detectors

    International Nuclear Information System (INIS)

    This chapter describes the 140 ton Large Area Scintillation Detector (LASD) being constructed in the Homestake Mine and discusses plans for a one kiloton liquid scintillation solar neutrino detector. The LASD consists of a hollow box 8 m high X 8 m wide X 16 m long, constructed from 200 liquid scintillator modules. Topics considered include magnetic monopoles, neutrino bursts from collapsing stars, solar neutrinos (the status of the search for neutrinos from the Sun, solar neutrino detection with the Large Mass Scintillation Detector), detector electronics for the LASD, and the construction status. Twenty tons of liquid scintillator (out of a total requirement of 140) are currently being pumped into the modules

  15. Study of the characteristics of SiPMs matrix as a photosensor for the scintillation detectors

    CERN Document Server

    Dzaparova, I M; Gavrilyuk, Yu M; Petkov, V B; Sergeev, A V; Volchenko, V I; Yakimenko, S P; Yanin, A F

    2015-01-01

    The matrices formed of silicon photomultipliers (SiPMs) are very promising photosensors for the scintillation detectors. The use of SiPM matrices with appropriate optical collector gives, in principle, a possibility to do a snapshot of glowing track of charged particle traversing a scintillator. The prototype of such scintillation detector is under development now in INR RAS. The preliminary results of characterization study of the matrix ArrayC-60035-64P-PCB (SensL company) for the prototype of such detector are presented.

  16. Combined scintillation detector for gamma dose rate measurement

    Energy Technology Data Exchange (ETDEWEB)

    Viererbl, L.; Novakova, O.; Jursova, L. (Tesla, Premysleni (Czechoslovakia). Vyzkumny Ustav Pristroju Jaderne Techniky)

    1990-01-01

    The specifications are described of a newly developed scintillation detector, essentially consisting of a plastic scintillator completed with inorganic scintillators ZnS(Ag) and NaI(Tl). The gamma dose rate is derived from the photomultiplier anode current. The composition and sizes of the scintillators and the capsule are selected so as to minimise the energy dependence errors and directional dependence errors of the detector response over a wide range of energies and/or angles. (author).

  17. X-ray multi-energy radiography with scintillator-photodiode detectors

    OpenAIRE

    Naydenov, S. V.; Ryzhikov, V. D.; B.V. Grinyov; Lisetskaya, E. K.; Opolonin, A. D.; Kozin, D. N.

    2002-01-01

    For reconstruction of the spatial structure of many-component objects, it is proposed to use multi-radiography with detection of X-ray by combined detector arrays using detectors of ``scintillator-photodiode'' type. A theoretical model has been developed of multi-energy radiography for thickness measurements of multi-layered systems and systems with defects. Experimental studies of the sensitivity, output signal of various inspection systems based on scintillators $ZnSe(Te)$ and $CsI(Tl)$, an...

  18. Neutron spectroscopy with scintillation detectors using wavelets

    Science.gov (United States)

    Hartman, Jessica

    The purpose of this research was to study neutron spectroscopy using the EJ-299-33A plastic scintillator. This scintillator material provided a novel means of detection for fast neutrons, without the disadvantages of traditional liquid scintillation materials. EJ-299-33A provided a more durable option to these materials, making it less likely to be damaged during handling. Unlike liquid scintillators, this plastic scintillator was manufactured from a non-toxic material, making it safer to use, as well as easier to design detectors. The material was also manufactured with inherent pulse shape discrimination abilities, making it suitable for use in neutron detection. The neutron spectral unfolding technique was developed in two stages. Initial detector response function modeling was carried out through the use of the MCNPX Monte Carlo code. The response functions were developed for a monoenergetic neutron flux. Wavelets were then applied to smooth the response function. The spectral unfolding technique was applied through polynomial fitting and optimization techniques in MATLAB. Verification of the unfolding technique was carried out through the use of experimentally determined response functions. These were measured on the neutron source based on the Van de Graff accelerator at the University of Kentucky. This machine provided a range of monoenergetic neutron beams between 0.1 MeV and 24 MeV, making it possible to measure the set of response functions of the EJ-299-33A plastic scintillator detector to neutrons of specific energies. The response of a plutonium-beryllium (PuBe) source was measured using the source available at the University of Nevada, Las Vegas. The neutron spectrum reconstruction was carried out using the experimentally measured response functions. Experimental data was collected in the list mode of the waveform digitizer. Post processing of this data focused on the pulse shape discrimination analysis of the recorded response functions to remove the

  19. Submillimeter resolution in one-dimensional position measurements of γ-ray photons by using a CsI(Tl) scintillator coupled to a linear array of silicon drift detectors

    Science.gov (United States)

    Fiorini, C.; Labanti, C.; Perotti, F.

    2000-08-01

    We present the one-dimensional (1D) position and energy resolution results obtained by a γ-ray detector based on a single CsI(Tl) scintillator coupled to a linear array of silicon drift detectors (SDDs). The present prototype has been realized in order to investigate the basic performances of this new architecture in view of the realization of Anger cameras for 2D imaging in nuclear medicine, based on the use of SDDs instead of photomultiplier tubes. The SDD provides a high value of quantum efficiency to the scintillation light, typical of a silicon photodetector, and is moreover characterized by a lower value of electronics noise with respect to conventional silicon photodiodes, thanks to the low value of output capacitance. At 122 keV the present detector shows a position resolution better than 0.5 mm FWHM, and an energy resolution of about 13% FWHM. The experimental setup is described and the most significant experimental results are presented.

  20. Central Tracking Detector Based on Scintillating Fibres

    CERN Multimedia

    2002-01-01

    Scintillating fibres form a reasonable compromise for central tracking detectors in terms of price, resolution, response time, occupancy and heat production. \\\\ \\\\ New fluorescents with large Stokes shifts have been produced, capable of working without wavelength shifters. Coherent multibundles have been developed to achieve high packing fractions. Small segments of tracker shell have been assembled and beam tests have confirmed expectations on spatial resolution. An opto-electronic delay line has been designed to delay the track patterns and enable coincidences with a first level trigger. Replacement of the conventional phosphor screen anode with a Si pixel chip is achieved. This tube is called ISPA-tube and has already been operated in beam tests with a scintillating fibres tracker. \\\\ \\\\ The aim of the proposal is to improve hit densities for small diameter fibres by increasing the fraction of trapped light, by reducing absorption and reflection losses, by reflecting light at the free fibre end, and by inc...

  1. Scintillation arrays characterization for photon emission imaging

    CERN Document Server

    Pani, R; De Vincentis, G; Indovina, P L; Pellegrini, R; Scafe, R; Soluri, A; Trotta, G

    2002-01-01

    The use of position sensitive photomultiplier tubes (PSPMT) in Nuclear Medicine imaging has recently produced some major steps forward in this field. In fact a dedicated camera for the organ under examination can improve imaging performances. However, in order to maximize them, scintillating crystals arrays have to be employed. In this work 13 Csl(Tl), Csl(Na), Nal(Tl), YAP(Ce) arrays were tested. Square pixel active area ranged between 1x1 and 2x2 mm sup 2 and thickness from 1 to 10 mm. Light output and energy resolution responses versus photon energy and pixel thickness were measured using a standard bialkali PMT. Scintillation light spatial distribution were analyzed coupling Csl(Tl) arrays to a recently available multianode 16 channel linear array PMT. Light output study shown that Csl(Tl) is the best considered material, optimizing optical, mechanical requirements and costs. Light output as well as energy resolution resulted independent on pixel area, but strongly dependent on thickness. Csl(Tl), 1 mm th...

  2. Monte-Carlo simulation to determine detector efficiency of plastic scintillating fiber

    Institute of Scientific and Technical Information of China (English)

    Mohammad Mehdi NASSERI; MA Qing-Li; YIN Ze-Jie; WU Xiao-Yi

    2004-01-01

    Fundamental characteristics of the plastic scintillating fiber (PSF) as a detector for electromagnetic radiation (X & γ) are obtained by GEANT4 detector simulation tool package. The detector response to radiation with energy of 10~400 keV is found out. Energy deposition as well as detector efficiency (DE) of the PSF are studied. In order to make linear array of the PSF for imaging purpose, the optimum length of fiber is also estimated.

  3. Limits on the spatial resolution of monolithic scintillators read out by APD arrays.

    Science.gov (United States)

    van der Laan, D J Jan; Maas, Marnix C; Bruyndonckx, Peter; Schaart, Dennis R

    2012-10-21

    Cramér-Rao theory can be used to derive the lower bound on the spatial resolution achievable with position-sensitive scintillation detectors as a function of the detector geometry and the pertinent physical properties of the scintillator, the photosensor and the readout electronics. Knowledge of the Cramér-Rao lower bound (CRLB) can for example be used to optimize the detector design and to test the performance of the method used to derive position information from the detector signals. Here, this approach is demonstrated for monolithic scintillator detectors for positron emission tomography. Two detector geometries are investigated: a 20 × 10 × 10 mm(3) and a 20 × 10 × 20 mm(3) monolithic LYSO:Ce(3+) crystal read out by one or two Hamamatsu S8550SPL avalanche photodiode (APD) arrays, respectively. The results indicate that in these detectors the CRLB is primarily determined by the APD excess noise factor and the number of scintillation photons detected. Furthermore, it is shown that the use of a k-nearest neighbor (k-NN) algorithm for position estimation allows the experimentally obtained spatial resolution to closely approach the CRLB. The approach outlined in this work can in principle be applied to any scintillation detector in which position information is encoded in the distribution of the scintillation light over multiple photosensor elements. PMID:23001515

  4. Limits on the spatial resolution of monolithic scintillators read out by APD arrays

    International Nuclear Information System (INIS)

    Cramér–Rao theory can be used to derive the lower bound on the spatial resolution achievable with position-sensitive scintillation detectors as a function of the detector geometry and the pertinent physical properties of the scintillator, the photosensor and the readout electronics. Knowledge of the Cramér–Rao lower bound (CRLB) can for example be used to optimize the detector design and to test the performance of the method used to derive position information from the detector signals. Here, this approach is demonstrated for monolithic scintillator detectors for positron emission tomography. Two detector geometries are investigated: a 20 × 10 × 10 mm3 and a 20 × 10 × 20 mm3 monolithic LYSO:Ce3+ crystal read out by one or two Hamamatsu S8550SPL avalanche photodiode (APD) arrays, respectively. The results indicate that in these detectors the CRLB is primarily determined by the APD excess noise factor and the number of scintillation photons detected. Furthermore, it is shown that the use of a k-nearest neighbor (k-NN) algorithm for position estimation allows the experimentally obtained spatial resolution to closely approach the CRLB. The approach outlined in this work can in principle be applied to any scintillation detector in which position information is encoded in the distribution of the scintillation light over multiple photosensor elements. (paper)

  5. The Software Design of Data Acquisition for Scintillation Crystal Array Detector Based on wxWidgets%基于 wxWidgets 的闪烁晶体阵列探测器数据获取软件设计

    Institute of Scientific and Technical Information of China (English)

    成科; 苏弘; 孔洁; 杨海波; 陈金达; 杨振雷; 杜成名

    2014-01-01

    The software of data acquisition and analysis for scintillation crystal array detector readout electronics is presented in this paper .The software is developed based on wxWidgets framework , the modularized design method is employed in this system ,and the host computer communicates with front -end electronics through an USB bus.The software system can be divided into five modules that includes command interface module ,data acquisition module ,time and amplitude calibration module ,parameter measurement module and real -time dis-play module .The software has been successfully applied to a scintillation crystal array detector for debugging and testing the system .The results show that the software can be also used conveniently in front -end read-out electronics for other detectors ,and which has a broad application foreground .%介绍了一种用于闪烁晶体阵列探测器读出电子学的数据获取与分析读出软件。软件基于wxWidgets平台开发,采用了模块化设计,上位机通过USB总线与电子学硬件部分通信。软件系统包括命令行接口模块、数据采集模块、参数测量模块、时间和幅度校准模块以及实时显示模块。将软件应用于闪烁晶体阵列探测器系统的调试与测试,结果表明:软件可方便地应用于其它探测器前端电子学的读出系统中,具有广泛的应用前景。

  6. Elevator mechanism and method for scintillation detectors

    International Nuclear Information System (INIS)

    An elevator mechanism and method for raising and lowering radioactive samples through a shielded vertical counting chamber in a benchtop scintillation detector is described. The elevator mechanism adds little or nothing to the height of the detector by using an elongated flexible member such as a metal tape secured to the bottom of the elevator platform and extending downwardly through the counting chamber and its bottom shielding, where the tape is bent laterally for connection to a drive means. In the particular embodiment illustrated, the tape is bent laterally below the bottom shielding for the counting chamber, and then upwardly along or through one side of the shielding to a reel at the top of the shielding. The tape is wound onto the reel, and the reel is driven by a reversible motor which winds and unwinds the tape on the reel to raise and lower the elevator platform

  7. Semiconductor scintillator detector for gamma radiation

    International Nuclear Information System (INIS)

    Nowadays the devices employed to evaluate individual radiation exposition are based on dosimetric films and thermoluminescent crystals, whose measurements must be processed in specific transductors. Hence, these devices carry out indirect measurements. Although a new generation of detectors based on semiconductors which are employed in EPD's (Electronic Personal Dosemeters) being yet available, it high producing costs and large dimensions prevents the application in personal dosimetry. Recent research works reports the development of new detection devices based on photovoltaic PIN diodes, which were successfully employed for detecting and monitoring exposition to X rays. In this work, we step forward by coupling a 2mm anthracene scintillator NE1, which converts the high energy radiation in visible light, generating a Strong signal which allows dispensing the use of photomultipliers. A low gain high performance amplifier and a digital acquisition device are employed to measure instantaneous and cumulative doses for energies ranging from X rays to Gamma radiation up to 2 MeV. One of the most important features of the PIN diode relies in the fact that it can be employed as a detector for ionization radiation, since it requires a small energy amount for releasing electrons. Since the photodiode does not amplify the corresponding photon current, it must be coupled to a low gain amplifier. Therefore, the new sensor works as a scintillator coupled with a photodiode PIN. Preliminary experiments are being performed with this sensor, showing good results for a wide range of energy spectrum. (author)

  8. Large-scale liquid scintillation detectors for solar neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Benziger, Jay B.; Calaprice, Frank P. [Princeton University Princeton, Princeton, NJ (United States)

    2016-04-15

    Large-scale liquid scintillation detectors are capable of providing spectral yields of the low energy solar neutrinos. These detectors require > 100 tons of liquid scintillator with high optical and radiopurity. In this paper requirements for low-energy neutrino detection by liquid scintillation are specified and the procedures to achieve low backgrounds in large-scale liquid scintillation detectors for solar neutrinos are reviewed. The designs, operations and achievements of Borexino, KamLAND and SNO+ in measuring the low-energy solar neutrino fluxes are reviewed. (orig.)

  9. The Scintillator Purification System for the Borexino Solar Neutrino Detector

    CERN Document Server

    Benziger, J; Cadonati, L; Calaprice, F; Chen, M; Corsi, A; Cubaiu, A; Dalnoki-Veress, F; Di Pietro, G; Fernholz, R; Ford, R; Galbiati, C; Gazzana, S; Goretti, A; Harding, E; Ianni, Aldo; Ianni, Andrea; Kidner, S; Korga, G; Leung, M; Löser, F; Lombardi, P; McCarty, K; McKinsey, D; Montanari, D; Nelson, A; Orsini, M; Papp, L; Parmeggiano, S; Pocar, A; Salvo, C; Schimizzi, D; Shutt, T; Sonnenschein, A; Soricelli, F; Suvorov, Y

    2007-01-01

    Purification of the 278 tons of liquid scintillator and 889 tons of buffer shielding for the Borexino solar neutrino detector was performed with a system that combined distillation, water extraction, gas stripping and filtration. The purification of the scintillator achieved unprecedented low backgrounds for the large scale liquid scintillation detector. This paper describes the principles of operation, design, construction and commissioning of the purification system, and reviews the requirements and methods to achieve system cleanliness and leak-tightness.

  10. The scintillator solvent procurement for the Borexino solar neutrino detector

    International Nuclear Information System (INIS)

    This paper describes the procurement and the production quality control system of Pseudocumene, the scintillator solvent of the solar neutrino detector Borexino at the Laboratorio Nazionale del Gran Sasso (Italy). This material constitutes about 99.9% of the scintillator total mass, therefore being the most critical element for the radiopurity of the detector.

  11. GERmanium detector array, GERDA

    International Nuclear Information System (INIS)

    The GERmanium Detector Array, GERDA, is designed to search for 'neutrinoless double beta decay' (0ν2β) in 76Ge. The high-purity segmented Ge detectors will be directly submerged and operated in liquid N2 or Ar. The measurement of the half-life time of 0ν2β decay will provide information about the absolute neutrino mass scale and indirectly, the hierarchy. The design goal of GERDA is to reach a sensitivity of 0.2 eV on the effective Majorana neutrino mass (mββ). The GERDA experiment is located in hall A of the Grand Sasso national lab (LNGS) and the construction will start in 2006

  12. Performance comparison of scintillators for alpha particle detectors

    Science.gov (United States)

    Morishita, Yuki; Yamamoto, Seiichi; Izaki, Kenji; Kaneko, Junichi H.; Toui, Kohei; Tsubota, Youichi; Higuchi, Mikio

    2014-11-01

    Scintillation detectors for alpha particles are often used in nuclear fuel facilities. Alpha particle detectors have also become important in the research field of radionuclide therapy using alpha emitters. ZnS(Ag) is the most often used scintillator for alpha particle detectors because its light output is high. However, the energy resolution of ZnS(Ag)-based scintillation detectors is poor because they are not transparent. A new ceramic sample, namely the cerium doped Gd2Si2O7 (GPS) scintillator, has been tested as alpha particle detector and its performances have been compared to that one of three different scintillating materials: ZnS(Ag), GAGG and a standard plastic scintillator. The different scintillating materials have been coupled to two different photodetectors, namely a photomultiplier tube (PMT) and a Silicon Photo-multiplier (Si-PM): the performances of each detection system have been compared. Promising results as far as the energy resolution performances (10% with PMT and 14% with Si-PM) have been obtained in the case of GPS and GAGG samples. Considering the quantum efficiencies of the photodetectors under test and their relation to the emission wavelength of the different scintillators, the best results were achieved coupling the GPS with the PMT and the GAGG with the Si-PM

  13. LHCb : A Scintillating Fibre Trackind Detector for the LHCb Upgrade

    CERN Multimedia

    Lindner, Rolf

    2014-01-01

    LHCb is preparing the upgrade which is scheduled to be installed in 2018/19. The Scintillating Fibre (SciFi) Tracker will be designed to replace the current tracking system downstream of the magnet, required to run at an increased luminosity of 1 - 2 10$^{33}$ cm$^{-2}$s$^{-1}$ and to collect a total of 50fb$^{-1}$ of data. The readout of the detector will be at 40MHz, applying a full software based trigger for every single bunch crossing. The SciFi Tracker consists of 12 planes covering a total surface of 350 m2. Modules are based on 2.5 m long multilayer ribbons made of 250 um diameter scintillating fibres as the active medium and signal transport. Silicon photomultiplier (SiPM) arrays with 128 channels at a width of 250 um are used for the readout. The signals from the SiPMS are digitized on an ASIC chip before reconstructing the track hit position within an FPGA on the front-end board. Several challenges facing this detector and the significant progress over the last year will be presented regarding the p...

  14. Neutron detector using lithiated glass-scintillating particle composite

    Science.gov (United States)

    Wallace, Steven; Stephan, Andrew C.; Dai, Sheng; Im, Hee-Jung

    2009-09-01

    A neutron detector composed of a matrix of scintillating particles imbedded in a lithiated glass is disclosed. The neutron detector detects the neutrons by absorbing the neutron in the lithium-6 isotope which has been enriched from the natural isotopic ratio to a commercial ninety five percent. The utility of the detector is optimized by suitably selecting scintillating particle sizes in the range of the alpha and the triton. Nominal particle sizes are in the range of five to twenty five microns depending upon the specific scintillating particle selected.

  15. Monte Carlo simulation of a single detector unit for the neutron detector array NEDA

    OpenAIRE

    Jaworski, G.; Palacz, M.; Nyberg, Johan; De Angelis, G.; de France, G; Nitto, A. Di; Egea, J.; Erduran, M. N.; Ertürk, S.; Farnea, E.; Gadea, A.; V González; Gottardo, A.(Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro, I-35020, Italy); Hüyük, T.; Kownacki, J.

    2012-01-01

    A study of the dimensions and performance of a single detector of the future neutron detector array NEDA was performed by means of Monte Carlo simulations, using GEANT4. Two different liquid scintillators were evaluated: the hydrogen based BC501A and the deuterated BC537. The efficiency and the probability that one neutron will trigger a signal in more than one detector were investigated as a function of the detector size. The simulations were validated comparing the results to experimental m...

  16. Scintillation Particle Detectors Based on Plastic Optical Fibres and Microfluidics

    CERN Document Server

    Mapelli, Alessandro; Renaud, Philippe

    2011-01-01

    This thesis presents the design, development, and experimental validation of two types of scintillation particle detectors with high spatial resolution. The first one is based on the well established scintillating fibre technology. It will complement the ATLAS (A Toroidal Large ApparatuS) detector at the CERN Large Hadron Collider (LHC). The second detector consists in a microfabricated device used to demonstrate the principle of operation of a novel type of scintillation detector based on microfluidics. The first part of the thesis presents the work performed on a scintillating fibre tracking system for the ATLAS experiment. It will measure the trajectory of protons elastically scattered at very small angles to determine the absolute luminosity of the CERN LHC collider at the ATLAS interaction point. The luminosity of an accelerator characterizes its performance. It is a process-independent parameter that is completely determined by the properties of the colliding beams and it relates the cross section of a ...

  17. Improved Scintillator Materials For Compact Electron Antineutrino Detectors

    NARCIS (Netherlands)

    Dijkstra, Peter; Wortche, Heinrich J.; Browne, Wesley R.

    2012-01-01

    Recent developments provide new components holding the potential to improve the performance of liquid scintillation electron antineutrino detectors used as nuclear reactors monitors. Current systems raise issues regarding size, quantum efficiency, stability, and spatial resolution of the vertex dete

  18. Precision beta gauge using a plastic scintillator and photomultiplier detector

    Energy Technology Data Exchange (ETDEWEB)

    Jaklevic, J.M.; Madden, N.W.; Wiegand, C.E. (Lawrence Berkely Lab., CA (USA))

    1983-09-01

    We describe the use of a plastic scintillator photomultiplier detector combination in applications involving the precision beta-gauge measurements of small mass deposits of thin substrates. The requisite precision (+- 2 ..mu..g/cm/sup 2/) places stringent requirements on the beta-particle counter and associated electronics. The scintillator based system is shown to be equivalent if not superior to previously employed semiconductor detectors with respect to long-term counting stability.

  19. Pulse shape discrimination studies in a liquid Argon scintillation detector

    OpenAIRE

    Pollmann, T.

    2007-01-01

    Liquid rare gases have been gaining popularity as detector media in rare event searches, especially dark matter experiments, and one factor driving their adoption is the possibility to recognise different types of ionizing radiation by the pulse shapes they evoke. This work on pulse shape discrimination in a liquid argon scintillation detector was done in the framework of the GERDA experiment, where liquid argon scintillation signals may be used for background suppression purposes. Liquid arg...

  20. X-ray multi-energy radiography with "scintillator-photodiode" detectors

    CERN Document Server

    Ryzhikov, V D; Grinyov, B V; Lisetskaya, E K; Opolonin, A D; Kozin, D N

    2002-01-01

    For reconstruction of the spatial structure of many-component objects, it is proposed to use multi-radiography with detection of X-ray by combined detector arrays using detectors of ``scintillator-photodiode'' type. A theoretical model has been developed of multi-energy radiography for thickness measurements of multi-layered systems and systems with defects. Experimental studies of the sensitivity, output signal of various inspection systems based on scintillators $ZnSe(Te)$ and $CsI(Tl)$, and object image reconstruction (with organics and non-ogranics materials singled out) have been carried out.

  1. Scintillating fiber detector development for the SSC: Annual progress report

    International Nuclear Information System (INIS)

    During the past year, considerable effort has been applied to the development of scintillating fiber detectors in several areas: new scintillation liquids and studies of their fluorescence properties; new fluorescent dyes based on non-intramolecular proton transfer; new dyes based on intramolecular proton transfer; incorporation of these new dyes in plastic (polystyrene) and liquid scintillation solutions; development of small cross section glass capillaries for the containment of liquid scintillators; studies of waveguide characteristics; studies of image intensifier phosphor screen characteristics; initial steps to form a collaboration to study and develop appropriate new properties of the Solid State Photomultiplier; construction of a new laboratory at Notre Dame to enhance our capabilities for further measurements and studies; and organization of and execution of a Workshop on Scintillating Fiber Detector Development for the SSC, held at Fermilab, November 14--16, 1988

  2. A region segmentation based algorithm for building crystal position lookup table in scintillation detector

    CERN Document Server

    Wang, Hai Peng; Liu, Shuang Quan; Fan, Xin; Cao, Xue Xiang; Chai, Pei; Shan, Bao Ci

    2014-01-01

    In scintillation detector, scintillation crystals are typically made into 2-dimension modular array. The location of incident gamma-ray need be calibrated due to spatial response nonlinearity. Generally, position histograms, the characteristic flood response of scintillation detectors, are used for position calibration. In this paper, a position calibration method based on crystal position lookup table which maps the inaccurate location calculated by Anger logic to the exact hitting crystal position has been proposed, Firstly, position histogram is segmented into disconnected regions. Then crystal marking points are labeled by finding the centroids of regions. Finally, crystal boundaries are determined and crystal position lookup table is generated. The scheme is evaluated by the whole-body PET scanner and breast dedicated SPECT detector developed by Institute of High Energy Physics, Chinese Academy of Sciences. The results demonstrate that the algorithm is accurate, efficient, robust and general purpose.

  3. Development of scintillation and luminescent detectors at BARC

    International Nuclear Information System (INIS)

    Research and development work carried out at the Bhabha Atomic Research Centre, Bombay, in the field of radiation detectors for various applications, particularly in the area of scintillation and luminescent detectors is reviewed. The review is presented in the form of 7 articles. (author). figs

  4. Study on Plastic Scintillation Detector Used in Very Terrible Environments

    International Nuclear Information System (INIS)

    A kind of plastic scintillation detector is developed to be used in very terrible environments. Each detector has two layers of damping structure and its main parts are not connected rigidly. These detectors can damp random vibration and adapt themselves to variation environments very well. Many environment experiments have been carried out such as random vibration, impact, high (low) temperature, high (low) air pressure, etc. All detectors work well and the output of most detectors changes less than 20%. This kind of detector can be used to measure neutron fluence in some special environments. (authors)

  5. Application of inorganic scintillator for neutron detector

    CERN Document Server

    Niki, N; Nakayama, S; Fushimi, K

    2003-01-01

    In a nuclear reactor institution, the neutron monitoring is indispensable in order to find an unusual neutron event which may be the signal of an accident or damage of a reactor. In this work, the possibility of a neutron monitor by means of an inorganic scintillator was researched. The detection efficiency and the intrinsic background of GSO scintillator and its sensitivity for neutrons have been studied.

  6. Photoelectron anticorrelations and sub-Poisson statistics in scintillation detectors

    OpenAIRE

    Bousselham, Abdelkader; Barrett, Harrison H.; Bora, Vaibhav; Shah, Kanai

    2010-01-01

    The performance of scintillation detectors for x rays and gamma rays is limited fundamentally by the statistics of the scintillation light and the resulting photoelectrons. This paper presents a new experimental approach to studying these statistics by observing correlations in the signals from two photodetectors. It is shown that the Fano factors (ratios of variance to mean), both for the number the photoelectrons produced on the photocathode of the photomultiplier and for the underlying num...

  7. Light output of EJ228 scintillation neutron detectors

    Energy Technology Data Exchange (ETDEWEB)

    Stevanato, L., E-mail: luca.stevanato@pd.infn.i [Dipartimento di Fisica dell' Universita di Padova, Via Marzolo 8, I-35131 Padova (Italy); Fabris, D. [INFN Sezione di Padova, Via Marzolo 8, I-35131 Padova (Italy); Hao, Xin [Dipartimento di Fisica dell' Universita di Padova, Via Marzolo 8, I-35131 Padova (Italy); Lunardon, M.; Moretto, S. [Dipartimento di Fisica dell' Universita di Padova, Via Marzolo 8, I-35131 Padova (Italy); INFN Sezione di Padova, Via Marzolo 8, I-35131 Padova (Italy); Nebbia, G.; Pesente, S. [INFN Sezione di Padova, Via Marzolo 8, I-35131 Padova (Italy); Sajo-Bohus, L. [Universidad Simon-Bolivar, Laboratorio Fisica Nuclear, Apartado 8900, 1080 A. Caracas (Venezuela, Bolivarian Republic of); Viesti, G. [Dipartimento di Fisica dell' Universita di Padova, Via Marzolo 8, I-35131 Padova (Italy); INFN Sezione di Padova, Via Marzolo 8, I-35131 Padova (Italy)

    2011-02-15

    The light output of neutron detectors based on the plastic scintillator EJ228 is studied as a function of neutron energy using a time tagged {sup 252}Cf source. Calibration of the light output scale is performed by fitting the experimental distribution of Compton scattering events of photons from a {sup 22}Na source with a response function obtained by Gaussian smearing of the predicted line-shape. The light output curve as well as the pulse height resolution for the EJ228 scintillators is very close (within 5%) to those recently reported for NE213 type organic liquid scintillators.

  8. The plastic scintillator detector calibration circuit for DAMPE

    Science.gov (United States)

    Yang, Haibo; Kong, Jie; Zhao, Hongyun; Su, Hong

    2016-07-01

    The Dark Matter Particle Explorer (DAMPE) is being constructed as a scientific satellite to observe high energy cosmic rays in space. Plastic scintillator detector array (PSD), developed by Institute of Modern Physics, Chinese Academy of Sciences (IMPCAS), is one of the most important parts in the payload of DAMPE which is mainly used for the study of dark matter. As an anti-coincidence detector, and a charged-particle identification detector, the PSD has a total of 360 electronic readout channels, which are distributed at four sides of PSD using four identical front end electronics (FEE). Each FEE reads out 90 charge signals output by the detector. A special calibration circuit is designed in FEE. FPGA is used for on-line control, enabling the calibration circuit to generate the pulse signal with known charge. The generated signal is then sent to the FEE for calibration and self-test. This circuit mainly consists of DAC, operation amplifier, analog switch, capacitance and resistance. By using controllable step pulse, the charge can be coupled to the charge measuring chip using the small capacitance. In order to fulfill the system's objective of large dynamic range, the FEE is required to have good linearity. Thus, the charge-controllable signal is needed to do sweep test on all channels in order to obtain the non-linear parameters for off-line correction. On the other hand, the FEE will run on the satellite for three years. The changes of the operational environment and the aging of devices will lead to parameter variation of the FEE, highlighting the need for regular calibration. The calibration signal generation circuit also has a compact structure and the ability to work normally, with the PSD system's voltage resolution being higher than 0.6%.

  9. Smaller, Lower-Power Fast-Neutron Scintillation Detectors

    Science.gov (United States)

    Patel, Jagdish; Blaes, Brent

    2008-01-01

    Scintillation-based fast-neutron detectors that are smaller and less power-hungry than mainstream scintillation-based fast-neutron detectors are undergoing development. There are numerous applications for such detectors in monitoring fast-neutron fluxes from nuclear reactors, nuclear materials, and natural sources, both on Earth and in outer space. A particularly important terrestrial application for small, low-power, portable fast-neutron detectors lies in the requirement to scan for nuclear materials in cargo and baggage arriving at international transportation facilities. The present development of miniature, low-power scintillation-based fast-neutron detectors exploits recent advances in the fabrication of avalanche photodiodes (APDs). Basically, such a detector includes a plastic scintillator, typically between 300 and 400 m thick with very thin silver mirror coating on all its faces except the one bonded to an APD. All photons generated from scintillation are thus internally reflected and eventually directed to the APD. This design affords not only compactness but also tight optical coupling for utilization of a relatively large proportion of the scintillation light. The combination of this tight coupling and the avalanche-multiplication gain (typically between 750 and 1,000) of the APD is expected to have enough sensitivity to enable monitoring of a fast-neutron flux as small as 1,000 cm(exp -2)s(exp -1). Moreover, pulse-height analysis can be expected to provide information on the kinetic energies of incident neutrons. It has been estimated that a complete, fully developed fast-neutron detector of this type, would be characterized by linear dimensions of the order of 10 cm or less, a mass of no more than about 0.5 kg, and a power demand of no more than a few watts.

  10. Performance of photomultiplier tubes and sodium iodide scintillation detector systems

    Science.gov (United States)

    Meegan, C. A.

    1981-01-01

    The performance of photomultiplier tubes (PMT's) and scintillation detector systems incorporating 50.8 by 1.27 cm NaI (T l) crystals was investigated to determine the characteristics of the photomultiplier tubes and optimize the detector geometry for the Burst and Transient Source Experiment on the Gamma Ray Observatory. Background information on performance characteristics of PMT's and NaI (T l) detectors is provided, procedures for measurement of relevant parameters are specified, and results of these measurements are presented.

  11. Performance of an X-ray imaging detector based on a structured scintillator

    Science.gov (United States)

    Svenonius, Olof; Sahlholm, Anna; Wiklund, Per; Linnros, Jan

    2009-08-01

    Structured scintillator plates have been fabricated by filling thallium-doped caesium iodide (CsI) into a silicon pore array. Their X-ray imaging properties have been characterized using a standard dental X-ray source and a charge coupled device (CCD) detector. Results indicate that finer structured pore arrays provide superior imaging resolution while their light output is lower. Direct absorption of X-ray quanta in the CCD is a significant contributor of detector noise. This can be avoided by using a thick fibre optic plate or, in certain cases, by using a hot-pixel software algorithm.

  12. Novel Scintillation Detectors for Prompt Fission γ-Ray Measurements

    Science.gov (United States)

    Billnert, R.; Andreotti, E.; Hambsch, F.-J.; Hult, M.; Karlsson, J.; Marissens, G.; Oberstedt, A.; Oberstedt, S.

    In this work we present first results from measurements of prompt fission γ-rays from the spontaneous fission in 252Cf. New and accurate data on corresponding γ-rays from the reactions 235U(nth,f) and 239Pu(nth,f) are highly demanded for the modeling of new Generation-IV nuclear reactor systems. For these experiments we employed scintillation detectors made out of new materials (LaBr3, LaCl3 and CeBr3), whose properties were necessary to know in order to obtain reliable results. Hence, we have characterized these detectors. In all the important properties these detectors outshine sodium-iodine detectors that where used in the 1970s, when the existing data had been acquired. Our finding is that the new generation of scintillation detectors is indeed promising, as far as an improved precision of the demanded data is concerned.

  13. Monte-Carlo simulation for determining SNR and DQE of linear array plastic scintillating fiber

    Institute of Scientific and Technical Information of China (English)

    Mohammad Mehdi NASSERI; MA Qing-Li; YIN Ze-Jie; WU Xiao-Yi

    2004-01-01

    Fundamental characteristics of the plastic-scintillating fiber (PSF) for wide energy range of electromagnetic radiation (X & γ) have been studied to evaluate possibility of using the PSF as an imaging detector for industrial purposes. Monte-Carlo simulation program (GEANT4.5.1, 2003) was used to generate the data. In order to evaluate image quality of the detector, fiber array was irradiated under various energy and fluxes. Signal to noise ratio (SNR)as well as detector quantum efficiency (DQE) were obtained.

  14. Inorganic scintillators for detector systems physical principles and crystal engineering

    CERN Document Server

    Lecoq, Paul; Korzhik, Mikhail

    2017-01-01

    This second edition features new chapters highlighting advances in our understanding of the behavior and properties of scintillators, and the discovery of new families of materials with light yield and excellent energy resolution very close to the theoretical limit. The book focuses on the discovery of next-generation scintillation materials and on a deeper understanding of fundamental processes. Such novel materials with high light yield as well as significant advances in crystal engineering offer exciting new perspectives. Most promising is the application of scintillators for precise time tagging of events, at the level of 100 ps or higher, heralding a new era in medical applications and particle physics. Since the discovery of the Higgs Boson with a clear signature in the lead tungstate scintillating blocks of the CMS Electromagnetic Calorimeter detector, the current trend in particle physics is toward very high luminosity colliders, in which timing performance will ultimately be essential to mitigating...

  15. Developing LAr Scintillation Light Collection Ideas in the Short Baseline Neutrino Detector

    Energy Technology Data Exchange (ETDEWEB)

    Szelc, A. M. [Manchester U.

    2016-02-08

    Scintillation light is becoming the most rapidly developing feature of Liquid Argon Time Projection Chamber (LArTPC) neutrino detectors due to its capability to enhance and expand their physics reach traditionally based on charge readout. The SBND detector, set to be built on the Booster Neutrino Beam Line at Fermilab, is in a unique position to test novel liquid argon scintillation light readout systems in a detector with physics neutrino events. The different ideas under consideration by the collaboration are described, including an array of PMTs detecting direct light, SiPM coupled lightguide bars and a setup which uses PMTs/SiPMS and wavelength shifter covered reflector foils, as well as their respective strengths and physics foci and the benchmarks used to compare them.

  16. Developing LAr scintillation light collection ideas in the Short Baseline Neutrino Detector

    International Nuclear Information System (INIS)

    Scintillation light is becoming the most rapidly developing feature of Liquid Argon Time Projection Chamber (LArTPC) neutrino detectors due to its capability to enhance and expand their physics reach traditionally based on charge readout. The SBND detector, set to be built on the Booster Neutrino Beam Line at Fermilab, is in a unique position to test novel liquid argon scintillation light readout systems in a detector with physics neutrino events. The different ideas under consideration by the collaboration are described, including an array of PMTs detecting direct light, SiPM coupled lightguide bars and a setup which uses PMTs/SiPMS and wavelength shifter covered reflector foils, as well as their respective strengths and physics foci and the benchmarks used to compare them

  17. Explore nuclearites in a large liquid scintillator neutrino detector

    CERN Document Server

    Guo, Wan-Lei; Lin, Tao; Wang, Zhi-Min

    2016-01-01

    We take the JUNO experiment as an example to explore nuclearites in the future large liquid scintillator detector. Comparing to the previous calculations, the visible energy of nuclearites across the liquid scintillator will be reestimated for the liquid scintillator based detector. Then the JUNO sensitivities to the nuclearite flux are presented. It is found that the JUNO projected sensitivities can be better than $7.7 \\times 10^{-17} {\\rm cm^{-2} s^{-1} sr^{-1}}$ for the nuclearite mass $10^{15} \\; {\\rm GeV} \\leq M \\leq 10^{24}$ GeV and initial velocity $10^{-4} \\leq \\beta_0 \\leq 10^{-1}$ with a 20 year running. Note that the JUNO will give the most stringent limits for downgoing nuclearites with $1.6 \\times 10^{13} \\; {\\rm GeV} \\leq M \\leq 4.0 \\times 10^{15}$ GeV and a typical galactic velocity $\\beta_0 = 10^{-3}$.

  18. Determination of spatial resolution of plastic scintillation fiber array with a simple method

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The spatial resolution of a position sensitive gamma-ray detector configuration based on plastic scintillation fiber array was measured using a Monte Carlo simulation method. Both point spread function and modulation transfer function (MTF) were presented. The factors that influence the spatial resolution were also discussed. The results of the simulation showed that the intrinsic spatial resolution was consistent with the size of the physical pixels and a few centimeters spatial resolution could be obtained under certain circumstances.

  19. The design of the totally active scintillator detector

    Science.gov (United States)

    Mefodiev, A. V.; Kudenko, Y. G.

    2015-11-01

    In the project of Advanced European Infrastructures for Detectors at Accelerators (AIDA), the Institute of Nuclear Research designed and tested the Totally Active Scintillator Detector (TASD). This paper reports the results of design of TASD prototype and outlines requirements for a test beam at CERN to test these, tentatively planned on the H8 beamline in the North Area, which is equipped with a large aperture magnet. TASD consists of 50 modules of plastic scintillators. Each module is instrumented with one X and one Y plane, with 90 scintillator bars per plane. The bar width, height and length are 1.0 cm, 0.7 cm and 90 cm respectively. The distance between modules can be varied from 0 to 2.5 cm. Other components such as active detectors or passive sheets of material can be inserted in these 2.5 cm gaps if required. The full detector depth can therefore be varied from 75 cm to 200 cm and in its compact form, it is 1 m3 in volume. The paper presents measurement results for the TASD elements that included in the prototype elements (measurement of crosscurrents, the light yield of scintillators, and the characteristics of photodiodes).

  20. Clinical prototype of a plastic water-equivalent scintillating fiber dosimeter array for QA applications

    International Nuclear Information System (INIS)

    A clinical prototype of a scintillating fiber dosimeter array for quality assurance applications is presented. The array consists of a linear array of 29 plastic scintillation detectors embedded in a water-equivalent plastic sheet coupled to optical fibers used to guide optical photons to a charge coupled device (CCD) camera. The CCD is packaged in a light-tight, radiation-shielded housing designed for convenient transport. A custom designed connector is used to ensure reproducible mechanical positioning of the optical fibers relative to the CCD. Profile and depth dose characterization measurements are presented and show that the prototype provides excellent dose measurement reproducibility (±0.8%) in-field and good accuracy (±1.6% maximum deviation) relative to the dose measured with an IC10 ionization chamber

  1. Measurement of some EAS properties using new scintillator detectors developed for the GRAPES-3 experiment

    Science.gov (United States)

    Grapes-3 Collaboration; Mohanty, P. K.; Dugad, S. R.; Goswami, U. D.; Gupta, S. K.; Hayashi, Y.; Iyer, A.; Ito, N.; Jagadeesan, P.; Jain, A.; Karthikeyan, S.; Kawakami, S.; Minamino, M.; Morris, S. D.; Nayak, P. K.; Nonaka, T.; Oshima, A.; Rao, B. S.; Ravindran, K. C.; Tanaka, H.; Tonwar, S. C.; GRAPES-3 Collaboration

    2009-02-01

    The GRAPES-3 extensive air shower (EAS) array started operation with 256 scintillator detectors at Ooty in India. Each detector is viewed by a fast photomultiplier tube (PMT) mounted at a height of 60 cm above the scintillator. However, for further expansion of the array, an alternative readout of the scintillator using wave-length shifting (WLS) fibers is employed. This resulted in improved performance with a larger photon signal and a more uniform response. With the inclusion of a second PMT, the dynamic range for particle detection has been increased to ˜5 × 103 particles m-2. We now use plastic scintillators, developed in-house to cut costs. The measurement of the density spectrum, shows a power law dependence with an index γ = 1.57 ± 0.04. Using the zenith angle dependence of the density spectrum, an attenuation length Λa = 98 106 g cm-2 for the EAS is obtained. These measurements are found to be consistent with the results reported earlier by other groups.

  2. Organic scintillator detector response simulations with DRiFT

    Science.gov (United States)

    Andrews, M. T.; Bates, C. R.; McKigney, E. A.; Solomon, C. J.; Sood, A.

    2016-09-01

    This work presents the organic scintillation simulation capabilities of DRiFT, a post-processing Detector Response Function Toolkit for MCNP® output. DRiFT is used to create realistic scintillation detector response functions to incident neutron and gamma mixed-field radiation. As a post-processing tool, DRiFT leverages the extensively validated radiation transport capabilities of MCNP® 6 , which also provides the ability to simulate complex sources and geometries. DRiFT is designed to be flexible, it allows the user to specify scintillator material, PMT type, applied PMT voltage, and quenching data used in simulations. The toolkit's capabilities, which include the generation of pulse shape discrimination plots and full-energy detector spectra, are demonstrated in a comparison of measured and simulated neutron contributions from 252Cf and PuBe, and photon spectra from 22Na and 228Th sources. DRiFT reproduced energy resolution effects observed in EJ-301 measurements through the inclusion of scintillation yield variances, photon transport noise, and PMT photocathode and multiplication noise.

  3. Position Reconstruction in a Dual Phase Xenon Scintillation Detector

    CERN Document Server

    Solovov, V N; Akimov, D Yu; Araújo, H M; Barnes, E J; Burenkov, A A; Chepel, V; Currie, A; DeViveiros, L; Edwards, B; Ghag, C; Hollingsworth, A; Horn, M; Kalmus, G E; Kobyakin, A S; Kovalenko, A G; Lebedenko, V N; Lindote, A; Lopes, M I; Lüscher, R; Majewski, P; Murphy, A St J; Neves, F; Paling, S M; da Cunha, J Pinto; Preece, R; Quenby, J J; Reichhart, L; Scovell, P R; Silva, C; Smith, N J T; Smith, P F; Stekhanov, V N; Sumner, T J; Thorne, C; Walker, R J

    2011-01-01

    We studied the application of statistical reconstruction algorithms, namely maximum likelihood and least squares methods, to the problem of event reconstruction in a dual phase liquid xenon detector. An iterative method was developed for in-situ reconstruction of the PMT light response functions from calibration data taken with an uncollimated gamma-ray source. Using the techniques described, the performance of the ZEPLIN-III dark matter detector was studied for 122 keV gamma-rays. For the inner part of the detector (R<100 mm), spatial resolutions of 13 mm and 1.6 mm FWHM were measured in the horizontal plane for primary and secondary scintillation, respectively. An energy resolution of 8.1% FWHM was achieved at that energy. The possibility of using this technique for improving performance and reducing cost of scintillation cameras for medical applications is currently under study.

  4. High Energy Neutrino Physics with Liquid Scintillation Detectors

    CERN Document Server

    Learned, John G

    2009-01-01

    Large liquid scintillation detectors have been generally dedicated to low energy neutrino measurements, in the MeV energy region (as for example, KamLAND and Borexino). Herein we describe the potential employment of large detectors (>1 kiloton) for studies of higher energy neutrinos interactions, from the cosmic rays and as a long baseline neutrino detector. Generally when people have considered large new instruments such as Hanohano and LENA, they have abandoned the possibility of doing useful measurements with higher energy neutrino interactions since these produce enough light to illuminate every photomultiplier tube, and the scintillation light is isotropic. Here we take into account Fermat's principle, which tells us that indeed the first light to reach the PMTs will be on or near the lightcone, the "Fermat surface", and that directional track information is available. Moreover we have realized that particle type distinction is possible (quasi-elastic muons from electrons). In fact the resolution from a ...

  5. The Plastic Scintillator Detector of the DAMPE space experiment

    Science.gov (United States)

    Sun, Zhiyu

    2016-07-01

    The DArk Matter Explorer (DAMPE) is a satellite based experiment aiming for dark matter search and many other topics astronomy interested. The Plastic Scintillator Detector (PSD) gives DAMPE the ability to measure charge of the crossing particles and separate gamma from electrons, which are necessary for achieving the goals of the experiment. The PSD is composed by 82 scintillator counters and read at both ends by a total of 162 photomultiplier tubes. In this paper, we describe the final design of DAMPE-PSD, the expected performances, and shows some results of the beam test carried on at CERN.

  6. Monte Carlo simulation of a very high resolution thermal neutron detector composed of glass scintillator microfibers.

    Science.gov (United States)

    Song, Yushou; Conner, Joseph; Zhang, Xiaodong; Hayward, Jason P

    2016-02-01

    In order to develop a high spatial resolution (micron level) thermal neutron detector, a detector assembly composed of cerium doped lithium glass microfibers, each with a diameter of 1 μm, is proposed, where the neutron absorption location is reconstructed from the observed charged particle products that result from neutron absorption. To suppress the cross talk of the scintillation light, each scintillating fiber is surrounded by air-filled glass capillaries with the same diameter as the fiber. This pattern is repeated to form a bulk microfiber detector. On one end, the surface of the detector is painted with a thin optical reflector to increase the light collection efficiency at the other end. Then the scintillation light emitted by any neutron interaction is transmitted to one end, magnified, and recorded by an intensified CCD camera. A simulation based on the Geant4 toolkit was developed to model this detector. All the relevant physics processes including neutron interaction, scintillation, and optical boundary behaviors are simulated. This simulation was first validated through measurements of neutron response from lithium glass cylinders. With good expected light collection, an algorithm based upon the features inherent to alpha and triton particle tracks is proposed to reconstruct the neutron reaction position in the glass fiber array. Given a 1 μm fiber diameter and 0.1mm detector thickness, the neutron spatial resolution is expected to reach σ∼1 μm with a Gaussian fit in each lateral dimension. The detection efficiency was estimated to be 3.7% for a glass fiber assembly with thickness of 0.1mm. When the detector thickness increases from 0.1mm to 1mm, the position resolution is not expected to vary much, while the detection efficiency is expected to increase by about a factor of ten.

  7. Radioactivity prospecting with plastic scintillator detector

    International Nuclear Information System (INIS)

    A location of buried fault is of particular concern for the development of groundwater resources in the rocky mountainous areas because groundwater tend to occur around the fault. The gamma-ray radioactivity prospecting with the NaI detector is one of tools to detect the location of buried fault and was successful in some regions. However, few studies on the relationships between the fault, groundwater, and the gamma-ray were reported. The buried fault in the dam-site where the surface soil was stripped showed that many springs were observed along the fissures in granodiorite of CM and CH levels on the both sides of the main fault zone. The radioactivity prospecting across the main fault zone showed that 214Bi and 214Bi/208Tl decrease over the main fault zone. These phenomena are interpreted as the leaching of the uranium. The fluctuation of 222Rn concentration showed the peak at the point near the f1 fault. 222Rn concentration over the areas of springs showed the low concentration. The high 222Rn concentration did not have any influence on 214Bi and 214Bi/208Tl. Our results request the rethinking of the current principle of the gamma-ray radioactivity prospecting that the reason of high 214Bi is caused by upward 222Rn along the open cracks in fault zone. The NaI detector for the radioactivity prospecting is heavy and expensive. PS detector is lightweight and inexpensive compared with NaI detectors. In order to make a large-scale detector with low price, a three-layered PS detector has been developed. Experiments show that the PS detector can discriminate the energies of gamma-rays. (author)

  8. Photoelectron anticorrelations and sub-Poisson statistics in scintillation detectors.

    Science.gov (United States)

    Bousselham, Abdelkader; Barrett, Harrison H; Bora, Vaibhav; Shah, Kanai

    2010-08-01

    The performance of scintillation detectors for x rays and gamma rays is limited fundamentally by the statistics of the scintillation light and the resulting photoelectrons. This paper presents a new experimental approach to studying these statistics by observing correlations in the signals from two photodetectors. It is shown that the Fano factors (ratios of variance to mean), both for the number the photoelectrons produced on the photocathode of the photomultiplier and for the underlying number of scintillation photons, can be deduced from these correlations. For LaBr(3)(Ce) and 662 keV gamma rays, the photopeak signals obtained by photomultipliers on opposite faces of a thin sample are negatively correlated, and the Fano factor for the photoelectrons is significantly less than one. The inferred Fano factor for the optical photons is very small, indistinguishable from zero within experimental error. PMID:20725609

  9. LORA: A scintillator array for LOFAR to measure extensive air showers

    International Nuclear Information System (INIS)

    The measurement of the radio emission from extensive air showers, induced by high-energy cosmic rays, is one of the key science projects of the LOFAR radio telescope. The LOfar Radboud air shower Array (LORA) has been installed in the core of LOFAR in the Netherlands. The main purpose of LORA is to measure the properties of air showers and to trigger the read-out of the LOFAR radio antennas to register extensive air showers. The experimental set-up of the array of scintillation detectors and its performance are described

  10. A Minor Modification of Leading Edge Discriminator Circuitry with a Delay Line for Baseline Restoration of Scintillation Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Izumi, N

    2003-05-27

    Multi-channel neutron time-of-flight detector arrays LaNSA, T-ion, Medusa, and Mandala, have been used for neutron spectroscopy in inertial confinement fusion experiments. These multi-channel neutron detector arrays consist of many identical scintillation detectors (842 {approx} 1024 channel), data acquisition electronics (discriminators, time-to digital converters, and controller). Each detector element is operated in neutron counting mode. Time-of-flight of individual detected neutrons are recorded by time to digital converters. The energy of each detected neutrons is determined from its time-of-flight. The accurate time measurement ({Delta}t {approx} 0.5 ns) and straightforward statistical features of the data obtained with these systems provides good integrity and reliability. The elements detector used in these systems are organic scintillators coupled with photo multiplier tubes. A scintillation detector operated in particle-counting mode requires finite recovery time after each detection event. The recovery time is determined by the time responses of scintillators, photo multiplier tubes, and the dead times of following discriminators and time-to digital converters. The harsh gamma ray background environment of fast ignitor experiments requires detectors that have fast recovery times. In high intensity laser experiments (I > 10{sup 19} W/cm{sup 2}), strong gamma ray bursts are produced by relativistic laser plasma interactions. Prior to the neutron signal, these strong gamma ray bursts hit the detectors and interfere with the detection of following neutron signals. In these situations, the recovery time of the system after preceding gamma ray bursts is determined mainly by the base line shift of the PMT signal (due to slower decay components of scintillators ''after glow''). Discriminators cannot detect following signal pulses until the proceeding burst decays below its threshold voltage. The base line shift caused by the after glow

  11. Monopoles and the Homestake underground scintillation detector

    International Nuclear Information System (INIS)

    Together, the two new Homestake detectors will be used to search for slow, massive magnetic monopoles; to study the zenith angle distribution of neutrino-induced muons; to search for neutrino bursts from the gravitational collapse of massive stars; to measure the multiplicity and transverse momentum distributions of cosmic ray muons; and to study the composition of the primary cosmic rays. Both instruments have been described in detail elsewhere; the authors discuss here the capabilities of the underground device as a detector of slow magnetic monopoles

  12. New scintillating media based on liquid crystals for particle detectors

    CERN Document Server

    Barnik, M I; Vasilchenko, V G; Golovkin, S V; Medvedkov, A M; Soloviev, A S

    2000-01-01

    The study results of optical, photoluminiscent and scintillation properties of a liquid crystal 4-pentyl-4'-cyanobiphenyl are presented. The scintillation light output of this liquid crystal is about 35% of crystal anthracene, its main decay time constants are 4 and 14 ns, and the maximum of light emission spectrum is about 400 nm. The light output of a dissolution of green emitting light scintillation dopant R6 in the liquid crystal is about 120% of crystal anthracene. The light output of the frozen dissolution measured at -112 deg. C is about 2.5 times higher as observed at +20 deg. C. In the uniaxially oriented liquid crystal, the predominant intensity direction of emitted light is pointed perpendicular to the liquid crystal director and an appreciable part of the emitted light is elliptically polarized. The possibility to use scintillation properties of liquid crystals is considered both for the improvement of existing particle detector characteristics and for the creation of new gated particle detectors.

  13. Instrumentation for multi-detector arrays

    Indian Academy of Sciences (India)

    R K Bhowmik

    2001-07-01

    The new generation of detector arrays require complex instrumentation and data acquisition system to ensure increased reliability of operation, high degree of integration, software control and faster data handling capability. The main features of some of the existing multi-detector arrays like MSU 4 array, Gammasphere and Eurogam are summarized. The instrumentation for the proposed INGA array in India is discussed.

  14. Simulations of SiPM based scintillation detector for PANDA

    International Nuclear Information System (INIS)

    The Facility for Antiproton and Ion Research (FAIR) is a future project at GSI which will extend hadron physics studies up to the charm meson region using antiproton beams together with a state-of-the-art PANDA (acronym for antiProton ANnihilation at DArmstadt) detector. The physics aim, in a broader sense, is to address the fundamental problems of hadron physics and aspects of Quantum Chromo Dynamics (QCD) at low energies. The proposed work in India will consist of several parts: (i) development of a SiPM based scintillation tile hodoscope for TOF information, (ii) development of a luminosity detector (silicon strip detector), and (iii) simulation studies of these detectors design as well as physics case studies. The present paper reports the initial simulation studies that have been started at Nuclear Physics Division (NPD), BARC, on the silicon photomultiplier(SiPM) based fast scintillation detector (SciTil). The hardware development activities on this SciTil detector, that are also going on in parallel at NPD, has been reported in an another contribution to this proceedings

  15. Investigation of scintillation detectors for relativistic heavy ion calorimetry

    CERN Document Server

    Lozeva, R; Balabanski, D L; Gerl, J; Górska, M; Kojouharov, I; Kopatch, Y; Mandal, S; Schaffner, H; Wollersheim, H J

    2003-01-01

    The new DELTA E/E detection system, calorimeter telescope (CATE), for charge and mass determination of heavy ions at high energies (>=100 MeV/n) has been designed. CATE, a calorimeter telescope will consist of position sensitive Si detectors for DELTA E determination and scintillators, readout by either PIN diode or PMT, for total-E determination. Different scintillation detectors were tested with sup 1 sup 3 sup 0 Sn, sup 1 sup 8 sup 6 Pb, sup 1 sup 9 sup 7 Au and sup 2 sup 3 sup 8 U beams of (100-300) MeV/n ion energy. By properly selecting the beam species from the FRS and applying position corrections, an energy resolution of approx =0.5% FWHM was observed. The corresponding mass resolution of 1/200 is adequate for employment of CATE in the Fast Beam RISING campaign at GSI.

  16. Neutron detector array at IUAC: Design features and instrumentation developments

    Indian Academy of Sciences (India)

    P Sugathan; A Jhingan; K S Golda; T Varughese; S Venkataramanan; N Saneesh; V V Satyanarayana; S K Suman; J Antony; Ruby Shanti; K Singh; S K Saini; A Gupta; A Kothari; P Barua; Rajesh Kumar; J Zacharias; R P Singh; B R Behera; S K Mandal; I M Govil; R K Bhowmik

    2014-11-01

    The characteristics and performance of the newly commissioned neutron detector array at IUAC are described. The array consists of 100 BC501 liquid scintillators mounted in a semispherical geometry and are kept at a distance of 175 cm from the reaction point. Each detector is a 5″ × 5″ cylindrical cell coupled to 5″ diameter photomultiplier tube (PMT). Signal processing is realized using custom-designed home-made integrated electronic modules which perform neutron–gamma discrimination using zero cross timing and time-of-flight (TOF) technique. Compact custom-built high voltage power supply developed using DC–DC converters are used to bias the detector. The neutrons are recorded in coincidence with fission fragments which are detected using multi-wire proportional counters mounted inside a 1m diameter SS target chamber. The detectors and electronics have been tested off-line using radioactive sources and the results are presented.

  17. A directional gamma-ray detector based on scintillator plates

    Energy Technology Data Exchange (ETDEWEB)

    Hanna, D., E-mail: hanna@physics.mcgill.ca; Sagnières, L.; Boyle, P.J.; MacLeod, A.M.L.

    2015-10-11

    A simple device for determining the azimuthal location of a source of gamma radiation, using ideas from astrophysical gamma-ray burst detection, is described. A compact and robust detector built from eight identical modules, each comprising a plate of CsI(Tl) scintillator coupled to a photomultiplier tube, can locate a point source of gamma rays with degree-scale precision by comparing the count rates in the different modules. Sensitivity to uniform environmental background is minimal.

  18. The readout electronics for Plastic Scintillator Detector of DAMPE

    Science.gov (United States)

    Kong, Jie; Yang, Haibo; Zhao, Hongyun; Su, Hong; Sun, Zhiyu; Yu, Yuhong; JingZhe, Zhang; Wang, XiaoHui; Liu, Jie; Xiao, Guoqing; Ma, Xinwen

    2016-07-01

    The Dark Matter Particle Explorer (DAMPE) satellite, which launched in December 2015, is designed to find the evidence of the existence of dark matter particles in the universe via the detection of the high-energy electrons and gamma-ray particles produced possibly by the annihilation of dark matter particles. Plastic Scintillator Detector (PSD) is one of major part of the satellite payload, which is comprised of a crossed pair of layers with 41 plastic scintillator-strips, each read out from both ends by the same Hamamatsu R4443MOD2 photo-multiplier tubes (PMTs). In order to extend linear dynamic range of detector, PMTs read out each plastic scintillator-strip separately with two dynode pickoffs. Therefore, the readout electronics system comprises of four Front-end boards to receive the pulses from 328 PMTs and implement charge measurement, which is based on the Application Specific Integrated Circuit (ASIC) chip VA160, 16 bits ADC and FPGA. The electronics of the detector has been designed following stringent requirements on mechanical and thermal stability, power consumption, radiation hardness and double redundancy. Various experiments are designed and implemented to check the performance of the electronics, some excellent results has been achieved.According to experimental results analysis, it is proved that the readout electronics works well.

  19. Towards monolithic scintillator based TOF-PET systems: practical methods for detector calibration and operation

    Science.gov (United States)

    Borghi, Giacomo; Tabacchini, Valerio; Schaart, Dennis R.

    2016-07-01

    Gamma-ray detectors based on thick monolithic scintillator crystals can achieve spatial resolutions  PET), the application of monolithic scintillators has so far been hampered by the lengthy and complex procedures needed for position- and time-of-interaction estimation. Here, the algorithms previously developed in our group are revised to make the calibration and operation of a large number of monolithic scintillator detectors in a TOF-PET system practical. In particular, the k-nearest neighbor (k-NN) classification method for x,y-position estimation is accelerated with an algorithm that quickly preselects only the most useful reference events, reducing the computation time for position estimation by a factor of ~200 compared to the previously published k-NN 1D method. Also, the procedures for estimating the DOI and time of interaction are revised to enable full detector calibration by means of fan-beam or flood irradiations only. Moreover, a new technique is presented to allow the use of events in which some of the photosensor pixel values and/or timestamps are missing (e.g. due to dead time), so as to further increase system sensitivity. The accelerated methods were tested on a monolithic scintillator detector specifically developed for clinical PET applications, consisting of a 32 mm  ×  32 mm  ×  22 mm LYSO : Ce crystal coupled to a digital photon counter (DPC) array. This resulted in a spatial resolution of 1.7 mm FWHM, an average DOI resolution of 3.7 mm FWHM, and a CRT of 214 ps. Moreover, the possibility of using events missing the information of up to 16 out of 64 photosensor pixels is shown. This results in only a small deterioration of the detector performance.

  20. Hybrid Array of Gamma Ray Detectors (HAGRiD)

    Science.gov (United States)

    Smith, Karl; Grzywacz, R.; Jones, K. L.; Munoz, S.; Baugher, T.; Cizewski, J. A.; Ratkiewicz, A.; Pain, S. D.

    2015-10-01

    Transfer reactions and beta-decay studies are powerful tools to study nuclear structure and to provide insight into astrophysically important reactions that may be difficult to measure directly. Both types of studies are enhanced immensely by measuring a particle-gamma coincidence. For transfer reactions, gamma-ray measurements improve the resolution, aid in channel selection and lifetime measurements. To achieve these coincidences the Hybrid Array of Gamma Ray Detectors (HAGRiD) is being designed and constructed. This array would be coupled with the Oak Ridge Rutgers Barrel Array (ORRUBA) of silicon detectors, the Versatile Array of Neutron Detectors at Low Energy (VANDLE) and beta detection scintillators. Detector systems providing a particle-gamma coincidence have previously compromised the charged-particle angular resolution due to compact geometries used to increase the gamma efficiency. HAGRiD will be coupled with ORRUBA such that resolution is not sacrificed, requiring the new array to provide improved resolution and efficiency over NaI and increased portability and flexibility over germanium detectors; therefore, we have chosen to use LaBr3(Ce) crystals. We demonstrate the advantages of a coupled detector system and discuss the current status of the project.

  1. Neutron spectrometry with organic scintillation detector

    International Nuclear Information System (INIS)

    This work describes a fast neutron spectrometer using a stilbene crystal as head detector with pulse shape discrimination (P.S.D.) to reject gamma background. Tre experimental procedure involves the P.S.D., the measurements to calibrate the spectrometer and the corrections for several factors, mainly the non-linear response of the stilbene. Results of the measurements with the reaction D2(d,n)He3, and with an Am-Be neutron source are presented. It is also presented the measurement of the spectrum of the fast reactor CCRAl-1. (Author) 17 refs

  2. Study of the characteristics of a scintillation array and single pixels for nuclear medicine imaging applications

    Institute of Scientific and Technical Information of China (English)

    ZHU Jie; MA Hong-Guang; MA Wen-Yan; ZENG Hui; WANG Zhao-Min; XU Zi-Zong

    2009-01-01

    By using a pixelized Nal(T1) crystal array coupled to a R2486 PSPMT, the characteristics of the array and of a single pixel, such as the light output, energy resolution, peak-to-valley ratio (P/V) and imaging performance of the detector were studied. The pixel size of the NaI(TI) scintillation pixel array is 2 min×2 mm×5 mm. There are in total 484 pixels in a 22~22 matrix. In the pixel spectrum an average peak-to-valley ratio (P/V) of 16 was obtained. In the image of all the pixels, good values for the Peak-to-Valley ratios could be achieved, namely a mean of 17, a maximum of 45 and the average peak FWHM (the average value of intrinsic spatial resolution) of 2.3 mm. However, the PSPMT non-uniform response and the scintillation pixels array inhomogeneities degrade the imaging performance of the detector.

  3. The HERMES recoil detector. Particle identification and determination of detector efficiency of the scintillating fiber tracker

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Xianguo

    2009-11-15

    HERMES is a fixed target experiment using the HERA 27.6 GeV polarized electron/positron beams. With the polarized beams and its gas targets, which can be highly polarized, HERMES is dedicated to study the nucleon spin structure. One of its current physics programs is to measure deeply virtual Compton scattering (DVCS). In order to detect the recoiling proton the Recoil Detector was installed in the target region in the winter of 2005, taking data until the HERA-shutdown in the summer of 2007. The Recoil Detector measured energy loss of the traversing particles with its sub-detectors, including the silicon strip detector and the scintillating fiber tracker. This enables particle identification for protons and pions. In this work a systematic particle identification procedure is developed, whose performance is quantified. Another aspect of this work is the determination of the detector efficiency of the scintillating fiber tracker. (orig.)

  4. Organic liquid scintillation detector shape and volume impact on radiation portal monitors

    Science.gov (United States)

    Paff, Marc G.; Clarke, Shaun D.; Pozzi, Sara A.

    2016-07-01

    We have developed and tested a radiation portal monitor using organic liquid scintillation detectors. In order to optimize our system designs, neutron measurements were carried out with three organic liquid scintillation detectors of different shapes and sizes, along with a 3He radiation portal monitor (RPM) as a reference. The three liquids tested were a 7.62 cm diameter by 7.62 cm length cylindrical active volume organic liquid scintillation detector, a 12.7 cm diameter by 12.7 cm length cylindrical active volume organic liquid scintillation detector, and a 25 cm by 25 cm by 10 cm "paddle" shaped organic liquid scintillation detector. Background and Cf-252 neutron measurements were recorded to allow for a comparison of neutron intrinsic efficiencies as well as receiver operating characteristics (ROC) curves between detectors. The 12.7 cm diameter cylindrical active volume organic liquid scintillation detector exhibited the highest intrinsic neutron efficiency (54%) of all three liquid scintillators. An ROC curve analysis for a heavily moderated Cf-252 measurement showed that using the 12.7 cm diameter by 12.7 cm length cylindrical active volume Eljen EJ309 organic liquid scintillation detector would result in the fewest needed detector units in order to achieve a near 100% positive neutron alarm rate while maintaining a better than 1 in 10,000 false alarm rate on natural neutron background. A small number of organic liquid scintillation detectors could therefore be a valid alternative to 3He in some RPM applications.

  5. Numerical evaluation of the light transport properties of alternative He-3 neutron detectors using ceramic scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Ohzu, A., E-mail: ohzu.akira@jaea.go.jp [Nuclear Science and Engineering Center, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); Takase, M.; Haruyama, M.; Kurata, N.; Kobayashi, N.; Kureta, M. [Nuclear Science and Engineering Center, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); Nakamura, T.; Toh, K.; Sakasai, K.; Suzuki, H.; Soyama, K. [J-PARC, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); Seya, M. [Integrated Support Center for Nuclear Nonproliferation and Nuclear Security, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan)

    2015-10-21

    The light transport properties of scintillator light inside alternative He-3 neutron detectors using scintillator sheets have been investigated by a ray-tracing simulation code. The detector consists of a light-reflecting tube, a thin rectangular ceramic scintillator sheet laminated on a glass plate, and two photo-multiplier tubes (PMTs) mounted at both ends of the detector tube. The flashes of light induced on the surface of the scintillator sheet via nuclear interaction between the scintillator and neutrons are detected by the two PMTs. The light output at both ends of various detectors in which the scintillator sheets are installed with several different arrangements were examined and evaluated in comparison with experimental results. The results derived from the simulation reveal that the light transport property is strongly dependent on the arrangement of the scintillator sheet inside the tube and the shape of the tube.

  6. Capillary detector with deuterated scintillator for inertial confinement fusion neutron images

    International Nuclear Information System (INIS)

    We demonstrate 325 μm spatial resolution in a 14 MeV neutron detector made with a capillary array filled with a deuterated liquid scintillator. A 10 μm source resolution in an image formed by 14 MeV neutrons is now achievable on a 25 m line-of-sight path for implosions at the Laser Mega Joule and the National Ignition Facilities. Analysis of penumbral and annular imaging techniques using this capillary array technology predicts good signal-to-noise ratios for images formed by targets yielding 1015 neutrons or more. Experimental images of individual scattered recoil ions and measurement of their resulting light distributions are presented and are well understood. Neutron imaging of deuterium-filled capsules is also found to be feasible, based on the light-yield calibration of the neutron detector

  7. Neutron response function characterization of 4He scintillation detectors

    International Nuclear Information System (INIS)

    Time-of-flight measurements were conducted to characterize the neutron energy response of pressurized 4He fast neutron scintillation detectors for the first time, using the Van de Graaff generator at Ohio University. The time-of-flight spectra and pulse height distributions were measured. This data was used to determine the light output response function, which was found to be linear at energies below 3.5 MeV. The intrinsic efficiency of the detector as a function of incident energy was also calculated: the average efficiency up to 10 MeV was 3.1%, with a maximum efficiency of 6.6% at 1.05 MeV. These results will enable development of neutron spectrum unfolding algorithms for neutron spectroscopy applications with these detectors

  8. Neutron response function characterization of {sup 4}He scintillation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Kelley, Ryan P.; Rolison, Lucas M.; Lewis, Jason M. [University of Florida, Nuclear Engineering Program, Gainesville, FL 32611-6400 (United States); Murer, David [Arktis Radiation Detectors Ltd., Räffelstrasse 11, 8045 Zürich (Switzerland); Massey, Thomas N. [Ohio University, Institute of Nuclear and Particle Physics, Athens, OH 45701 (United States); Enqvist, Andreas; Jordan, Kelly A. [University of Florida, Nuclear Engineering Program, Gainesville, FL 32611-6400 (United States)

    2015-09-01

    Time-of-flight measurements were conducted to characterize the neutron energy response of pressurized {sup 4}He fast neutron scintillation detectors for the first time, using the Van de Graaff generator at Ohio University. The time-of-flight spectra and pulse height distributions were measured. This data was used to determine the light output response function, which was found to be linear at energies below 3.5 MeV. The intrinsic efficiency of the detector as a function of incident energy was also calculated: the average efficiency up to 10 MeV was 3.1%, with a maximum efficiency of 6.6% at 1.05 MeV. These results will enable development of neutron spectrum unfolding algorithms for neutron spectroscopy applications with these detectors.

  9. Emulation workbench for position sensitive gaseous scintillation detectors

    Science.gov (United States)

    Pereira, L.; Margato, L. M. S.; Morozov, A.; Solovov, V.; Fraga, F. A. F.

    2015-12-01

    Position sensitive detectors based on gaseous scintillation proportional counters with Anger-type readout are being used in several research areas such as neutron detection, search for dark matter and neutrinoless double beta decay. Design and optimization of such detectors are complex and time consuming tasks. Simulations, while being a powerful tool, strongly depend on the light transfer models and demand accurate knowledge of many parameters, which are often not available. Here we describe an alternative approach based on the experimental evaluation of a detector using an isotropic point-like light source with precisely controllable light emission properties, installed on a 3D positioning system. The results obtained with the developed setup at validation conditions, when the scattered light is strongly suppressed show good agreement with simulations.

  10. Emulation workbench for position sensitive gaseous scintillation detectors

    CERN Document Server

    Pereira, L; Morozov, A; Solovov, V; Fraga, F A F

    2015-01-01

    Position sensitive detectors based on gaseous scintillation proportional counters with Anger-type readout are being used in several research areas such as neutron detection, search for dark matter and neutrinoless double beta decay. Design and optimization of such detectors are complex and time consuming tasks. Simulations, while being a powerful tool, strongly depend on the light transport models and demand accurate knowledge of many parameters, which are often not available. Here we describe an alternative approach based on the experimental evaluation of a detector using an isotropic point-like light source with precisely controllable light emission properties, installed on a 3D positioning system. The results obtained with the developed setup at validation conditions, when the scattered light is strongly suppressed, show good agreement with simulations.

  11. Improving Photoelectron Counting and Particle Identification in Scintillation Detectors with Bayesian Techniques

    CERN Document Server

    Akashi-Ronquest, M; Batygov, M; Beltran, B; Bodmer, M; Boulay, M G; Broerman, B; Buck, B; Butcher, A; Cai, B; Caldwell, T; Chen, M; Chen, Y; Cleveland, B; Coakley, K; Dering, K; Duncan, F A; Formaggio, J A; Gagnon, R; Gastler, D; Giuliani, F; Gold, M; Golovko, V V; Gorel, P; Graham, K; Grace, E; Guerrero, N; Guiseppe, V; Hallin, A L; Harvey, P; Hearns, C; Henning, R; Hime, A; Hofgartner, J; Jaditz, S; Jillings, C J; Kachulis, C; Kearns, E; Kelsey, J; Klein, J R; Kuzniak, M; LaTorre, A; Lawson, I; Li, O; Lidgard, J J; Liimatainen, P; Linden, S; McFarlane, K; McKinsey, D N; MacMullin, S; Mastbaum, A; Mathew, R; McDonald, A B; Mei, D -M; Monroe, J; Muir, A; Nantais, C; Nicolics, K; Nikkel, J A; Noble, T; O'Dwyer, E; Olsen, K; Gann, G D Orebi; Ouellet, C; Palladino, K; Pasuthip, P; Perumpilly, G; Pollmann, T; Rau, P; Retiere, F; Rielage, K; Schnee, R; Seibert, S; Skensved, P; Sonley, T; Vazquez-Jauregui, E; Veloce, L; Walding, J; Wang, B; Wang, J; Ward, M; Zhang, C

    2014-01-01

    Many current and future dark matter and neutrino detectors are designed to measure scintillation light with a large array of photomultiplier tubes (PMTs). The energy resolution and particle identification capabilities of these detectors depend in part on the ability to accurately identify individual photoelectrons in PMT waveforms despite large variability in pulse amplitudes and pulse pileup. We describe a Bayesian technique that can identify the times of individual photoelectrons in a sampled PMT waveform without deconvolution, even when pileup is present. To demonstrate the technique, we apply it to the general problem of particle identification in single-phase liquid argon dark matter detectors. Using the output of the Bayesian photoelectron counting algorithm described in this paper, we construct several test statistics for rejection of backgrounds for dark matter searches in argon. Compared to simpler methods based on either observed charge or peak finding, the photoelectron counting technique improves ...

  12. Simulation results of liquid and plastic scintillator detectors for reactor antineutrino detection - A comparison

    International Nuclear Information System (INIS)

    A simulation study of two kinds of scintillation detectors has been done using GEANT4. We compare plastic scintillator and liquid scintillator based designs for detecting electron antineutrinos emitted from the core of reactors. The motivation for this study is to set up an experiment at the research reactor facility at BARC for very short baseline neutrino oscillation study and remote reactor monitoring

  13. Analysis of amplitude spectra with overlapping peaks from scintillation detectors

    International Nuclear Information System (INIS)

    A technique is proposed for resolution of overlapping peaks in amplitude spectra obtained by scintillation detectors. Based on the technique, a program was developed and is being used in practical measurements at Kozloduy NPP. The program works in environment of MathCAD, version 2, of the firm MathSoft, Inc. As regards the handling of amplitude spectra, a software emulation on an multichannel analyzer with a personal computer was developed. The language used for program emulation is QuickBASIC, version 4.0 of the firm Microsoft Corp. (author)

  14. A liquid scintillator detector with wavelength-shifting fibre readout

    CERN Document Server

    Doucet, M; Grégoire, G; Panman, J; Zucchelli, P

    2000-01-01

    A technique based on liquid scintillator with wavelength-shiftingfibre readout is interesting for large-mass neutrino detectors.In this paper we present the first results obtained with a laboratoryprototype assembled at CERN. In the configuration tested, a large light yield has been observed and attenuation lengths of the order of 3.2~m have been measured. As a comparison, we also measured the attenuation length of the fibres in air using the same setup. No significant difference in attenuation length between the fibres in air and in liquid was measured.

  15. The Seeding tracking algorithm for a scintillating detector at LHCb

    CERN Document Server

    Amhis, Y; De Cian, M; Nikodem, T; Polci, F

    2014-01-01

    The project of the LHCb upgraded detector foreseens the presence of a Scintillating Fiber Tracker (SciFi). This note describes the algorithm used for reconstructing standalone tracks in the SciFi, called $Seeding$. This algorithm is crucial for reconstructing tracks generated by long lived particles such as $K^0_s$. The main performances on simulated samples for running conditions expected in future data taking after the upgrade, namely a luminosity larger than $\\mathcal{L} = 2 \\times 10^{33} cm^{-2}s^{1}$, are also discussed.

  16. Towards monolithic scintillator based TOF-PET systems: practical methods for detector calibration and operation

    Science.gov (United States)

    Borghi, Giacomo; Tabacchini, Valerio; Schaart, Dennis R.

    2016-07-01

    Gamma-ray detectors based on thick monolithic scintillator crystals can achieve spatial resolutions  NN) classification method for x,y-position estimation is accelerated with an algorithm that quickly preselects only the most useful reference events, reducing the computation time for position estimation by a factor of ~200 compared to the previously published k-NN 1D method. Also, the procedures for estimating the DOI and time of interaction are revised to enable full detector calibration by means of fan-beam or flood irradiations only. Moreover, a new technique is presented to allow the use of events in which some of the photosensor pixel values and/or timestamps are missing (e.g. due to dead time), so as to further increase system sensitivity. The accelerated methods were tested on a monolithic scintillator detector specifically developed for clinical PET applications, consisting of a 32 mm  ×  32 mm  ×  22 mm LYSO : Ce crystal coupled to a digital photon counter (DPC) array. This resulted in a spatial resolution of 1.7 mm FWHM, an average DOI resolution of 3.7 mm FWHM, and a CRT of 214 ps. Moreover, the possibility of using events missing the information of up to 16 out of 64 photosensor pixels is shown. This results in only a small deterioration of the detector performance.

  17. Characterization of array scintillation detector for follicle thyroid 2D imaging acquisition using Monte Carlo simulation; Caracterizacao de uma matriz detectora cintiladora para aquisicao de imagem 2D da regiao folicular da glandula tireoide por emissao radioativa usando simulacao Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Carlos Borges da

    2007-05-15

    The image acquisition methods applied to nuclear medicine and radiobiology are a valuable research study for determination of thyroid anatomy to seek disorders associated to follicular cells. The Monte Carlo (MC) simulation has also been used in problems related to radiation detection in order to map medical images since the improvement of data processing compatible with personnel computers (PC). This work presents an innovative study to find out the adequate scintillation inorganic detector array that could be coupled to a specific light photo sensor, a charge coupled device (CCD) through a fiber optic plate in order to map the follicles of thyroid gland. The goal is to choose the type of detector that fits the application suggested here with spatial resolution of 10 {mu}m and good detector efficiency. The methodology results are useful to map a follicle image using gamma radiation emission. A source - detector simulation is performed by using a MCNP4B (Monte Carlo for Neutron Photon transport) general code considering different source energies, detector materials and geometries including pixel sizes and reflector types. The results demonstrate that by using MCNP4B code is possible to searching for useful parameters related to the systems used in nuclear medicine, specifically in radiobiology applied to endocrine physiology studies to acquiring thyroid follicles images. (author)

  18. Application of scintillating fiber gamma ray detectors for medical imaging

    International Nuclear Information System (INIS)

    The recently developed plastic scintillating fiber technology started the development of a new generation of high spatial and time resolution gamma ray detectors for medical imaging, such as positron emission tomography (PET) and single photon emission computed tomography (SPECT). A scintillating fiber PET module consisting of two 5 x 5 x 2.5 cm3 detector stacks made of parallel 1.0 mm diameter fiber, separated by 20 cm, each viewed by a Hamamatsu R2486 position sensitive photomultiplier was developed and tested. The time resolution of the coincidence system is 10 nsec. The spatial resolution and efficiency of this module turned out to be 2.3 mm (FWHM) and 2.0%, respectively, and independent of the location of the 22Na testing source inside a sphere of 2 cm radius around the center of the two fiber stacks. The effects of gammas scattered in a 15 cm diameter water filled glass cylinder into which the 22Na was immersed did not change the spatial resolution of the system

  19. Fission-fragment detector for DANCE based on thin scintillating films

    Science.gov (United States)

    Rusev, G.; Roman, A. R.; Daum, J. K.; Springs, R. K.; Bond, E. M.; Jandel, M.; Baramsai, B.; Bredeweg, T. A.; Couture, A.; Favalli, A.; Ianakiev, K. D.; Iliev, M. L.; Mosby, S.; Ullmann, J. L.; Walker, C. L.

    2015-12-01

    A fission-fragment detector based on thin scintillating films has been built to serve as a trigger/veto detector in neutron-induced fission measurements at DANCE. The fissile material is surrounded by scintillating films providing 4 π detection of the fission fragments. The scintillation photons were registered with silicon photomultipliers. A measurement of the 235U (n , f) reaction with this detector at DANCE revealed a correct time-of-flight spectrum and provided an estimate for the efficiency of the prototype detector of 11.6(7)%. Design and test measurements with the detector are described.

  20. [Effects of ionizing radiation on scintillators and other particle detectors

    International Nuclear Information System (INIS)

    It is my task to summarise the great variety of topics (covering a refreshing mix of physics, chemistry and technology) presented at this conference, which has focused on the effects of ionising radiation on scintillators and other particle detectors. One of the reasons and the central interest of many of the participants was the use of such detectors in experiments at two future large hadron colliders: the Superconducting Super Collider to be operating outside of Dallas in the United States by the turn of the decade and its European counterpart the Large Hadron Collider to be operating outside of Geneva in Switzerland on a similar time scale. These accelerators are the ''apple of the high energy physicist's eye.'' Their goal is to uncover the elusive Higgs particle and thereby set the cornerstone in our current knowledge of elementary particle interactions. This is the Quest, and from this lofty height the presentations rapidly moved on to the specific questions of experimental science: how such an experiment is carried out; why radiation damage is an issue; how radiation damage affects detectors; which factors affect radiation damage characteristics; which factors are not affected by radiation damage; and how better detectors may be constructed. These were the substance of this conference

  1. Simulation and optimisation of a position sensitive scintillation detector with wavelength shifting fibers for thermal neutrons

    International Nuclear Information System (INIS)

    In neutron scattering experiments it is important to have position sensitive large scale detectors for thermal neutrons. A detector based on a neutron scintillator with wave length shifting fibers is a new kind of such a detector. We present the simulation of the detector based on the microscopic structure of the scintillation material of the mentioned detector. It consists of a converter and a scintillation powder bound in a matrix. The converter in our case is lithium fluoride with enriched lithium 6, to convert thermal neutrons into high energetic alpha and triton particles. The scintillation material is silver doped zinc sulfide. We show that pulse height spectra obtained by these scintillators can be be explained by the simple model of randomly distributed spheres of zinc sulfide and lithium fluoride. With this model, it is possible to optimise the mass ratio of zinc sulfide to lithium fluoride with respect to detection efficiency and/or energy deposition in zinc sulfide.

  2. Simulation and optimisation of a position sensitive scintillation detector with wavelength shifting fibers for thermal neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Herzkamp, Matthias; Engels, Ralf; Kemmerling, Guenter [ZEA-2, Forschungszentrum Juelich (Germany); Brueckel, Thomas [JCNS, Forschungszentrum Juelich (Germany); Stahl, Achim [III. Physikalisches Institut B, RWTH Aachen (Germany); Waasen, Stefan van [ZEA-2, Forschungszentrum Juelich (Germany); Faculty of Engineering, University of Duisburg-Essen (Germany)

    2015-07-01

    In neutron scattering experiments it is important to have position sensitive large scale detectors for thermal neutrons. A detector based on a neutron scintillator with wave length shifting fibers is a new kind of such a detector. We present the simulation of the detector based on the microscopic structure of the scintillation material of the mentioned detector. It consists of a converter and a scintillation powder bound in a matrix. The converter in our case is lithium fluoride with enriched lithium 6, to convert thermal neutrons into high energetic alpha and triton particles. The scintillation material is silver doped zinc sulfide. We show that pulse height spectra obtained by these scintillators can be be explained by the simple model of randomly distributed spheres of zinc sulfide and lithium fluoride. With this model, it is possible to optimise the mass ratio of zinc sulfide to lithium fluoride with respect to detection efficiency and/or energy deposition in zinc sulfide.

  3. Large Format Detector Arrays for Astrophysics

    Science.gov (United States)

    Moseley, Harvey

    2006-01-01

    Improvements in detector design and advances in fabrication techniques has resulted in devices which can reach fundamental sensitivity limits in many cases. Many pressing astrophysical questions require large arrays of such sensitive detectors. I will describe the state of far infrared through millimeter detector development at NASA/GSFC, the design and production of large format arrays, and the initial deployment of these powerful new tools.

  4. POSSuMUS: a position sensitive scintillating muon SiPM detector

    CERN Document Server

    Ruschke, Alexander

    The development of a modular designed large scale scintillation detector with a two-dimensional position sensitivity is presented in this thesis. This novel POsition Sensitive Scintillating MUon SiPM Detector is named POSSuMUS. The POSSuMUS detector is capable to determine the particle’s position in two space dimensions with a fast trigger capability. Each module is constructed from two trapezoidal shaped plastic scintillators to form one rectangular shaped detector module. Both trapezoids are optically insulated against each other. In both trapezoids the scintillation light is collected by plastic fibers and guided towards silicon photomultipliers (SiPMs). SiPMs are light sensors which are capable to detect even smallest amounts of light. By combining several detector modules, position sensitive areas from 100 cm2 to few m2 are achievable with few readout channels. Therefore, POSSuMUS provides a cost effective detector concept. The position sensitivity along the trapezoidal geometry of one detector module ...

  5. Measuring Fast Neutrons with Large Liquid Scintillation Detector for Ultra-low Background Experiments

    CERN Document Server

    Zhang, C; Davis, P; Woltman, B; Gray, F

    2013-01-01

    We developed a 12-liter volume neutron detector filled with the liquid scintillator EJ301 that measures neutrons in an underground laboratory where dark matter and neutrino experiments are located. The detector target is a cylindrical volume coated on the inside with reflective paint (95% reflectivity) that significantly increases the detector's light collection. We demonstrate several calibration techniques using point sources and cosmic-ray muons for energies up to 20 MeV for this large liquid scintillation detector. Neutron-gamma separation using pulse shape discrimination with a few MeV neutrons to hundreds of MeV neutrons is shown for the first time using a large liquid scintillator.

  6. Scintillating glass, fiber-optic plate detectors for tracking applications

    International Nuclear Information System (INIS)

    The authors studied the performance of scintillating glass fiber-optic plates using high energy particle beams at SLAC, Fermilab, and the ANLIPNS facility. The plates were composed of silicate glasses containing: (1) 5.4 weight % of Tb2O3 in cladded-glass fibers in a matrix of 15 μm spacing; and (2) 0.6 mole % of Ce2O3 in cladded-glass fibers in matrices of 10 μm and 25 μm spacing. The plates were viewed with a three-stage image intensifier. Particle tracks and nuclear interactions were recorded on film. The authors observed 5 detected hitsmm for minimum ionizing particles in the Tb glass, and -- 2 hitsmm for Ce glass. Preliminary measurements of attenuation length and radiation resistance properties of the Cerium glass which are of particular importance for collider applications, indicate that λ/sub atten/ > 10 cm for 10 μm diameter fibers and that dose rates in excess of 107 rads over a period of several days lead to a 20% loss of optical transmission near peak fluorescence (390 nm). The results of all these tests indicate that scintillating glass fiber-optic plates can be used in high spatial resolution tracking detectors for both fixed target and colliding beam experiments, and (in the case of Ce2O3 glass) high luminosity environments

  7. Linear position sensitive neutron detector using fiber optic encoded scintillators

    International Nuclear Information System (INIS)

    A linear position sensitive slow neutron detector with 3 mm resolution is described. It uses the fiber optic coding principle in which the resolution elements are separate pieces of lithium loaded glass scintillator each coupled by means of flexible polymer optical fibers to a unique combination of 3 photo multipliers (PM's) out of a bank of 12. A decoder circuit repsponds to a triple coincidence between PM outputs and generates a 12 bit work which identifies the scintillator element which stopped the incident neutron. Some details of the construction and decoding electronics are given together with test results obtained using a laboratory isotope neutron source and a monochomated, collimated neutron beam from a reactor. The count rate in the absence of neutron sources is 2 to 3 c min-1 per element; the element to element variation in response to a uniform flux is a few percent for 95% of the elements; the resolution as measured by a 1 mm wide prode neutron beam is 3 mm; the relative long term stability is about 0.1% over 3 days and the detection efficiency measured by comparison with an end windowed, high pressure gas counter is about 65% at a neutron wavelength of 0.9A0

  8. Spatially distributed scintillator arrays for diagnosing runaway electron transport and energy behavior in tokamaksa)

    Science.gov (United States)

    James, A. N.; Hollmann, E. M.; Tynan, G. R.

    2010-10-01

    We present details of a new bismuth germanate [Bi4Ge3O12 (BGO)] scintillator array used to diagnose the transport and energy behavior of runaway electrons (REs) in DIII-D. BGO exhibits important properties for these compact detectors including high light yield which sufficiently excites photodiode detectors (8500 photons/MeV), high density and atomic numbers of constituent materials which maximizes sensitivity, and relative neutron blindness which minimizes complications in data interpretation. The detectors observe primarily hard x-ray radiation emitted in a forward beamed pattern by RE when they strike first wall materials or bulk ions and neutrals in the plasma, although we also address photoneutron signals. The arrangement of the array enables time resolved location of x-ray emission and associated asymmetries which help identify instabilities and confinement properties of RE. By shielding a subset of detectors with different thicknesses of lead, and with interpretative support of the code EGSNRC, we also measure RE energy, although due to the often distributed nature of RE strike points and the forward beamed character of emitted hard x-rays, we restrict interpretation as a lower bound for RE energy.

  9. Spatially distributed scintillator arrays for diagnosing runaway electron transport and energy behavior in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    James, A. N.; Hollmann, E. M.; Tynan, G. R. [UC San Diego Center for Energy Research, La Jolla, California 92093-0417 (United States)

    2010-10-15

    We present details of a new bismuth germanate [Bi{sub 4}Ge{sub 3}O{sub 12} (BGO)] scintillator array used to diagnose the transport and energy behavior of runaway electrons (REs) in DIII-D. BGO exhibits important properties for these compact detectors including high light yield which sufficiently excites photodiode detectors (8500 photons/MeV), high density and atomic numbers of constituent materials which maximizes sensitivity, and relative neutron blindness which minimizes complications in data interpretation. The detectors observe primarily hard x-ray radiation emitted in a forward beamed pattern by RE when they strike first wall materials or bulk ions and neutrals in the plasma, although we also address photoneutron signals. The arrangement of the array enables time resolved location of x-ray emission and associated asymmetries which help identify instabilities and confinement properties of RE. By shielding a subset of detectors with different thicknesses of lead, and with interpretative support of the code EGSNRC, we also measure RE energy, although due to the often distributed nature of RE strike points and the forward beamed character of emitted hard x-rays, we restrict interpretation as a lower bound for RE energy.

  10. Spatially distributed scintillator arrays for diagnosing runaway electron transport and energy behavior in tokamaks

    International Nuclear Information System (INIS)

    We present details of a new bismuth germanate [Bi4Ge3O12 (BGO)] scintillator array used to diagnose the transport and energy behavior of runaway electrons (REs) in DIII-D. BGO exhibits important properties for these compact detectors including high light yield which sufficiently excites photodiode detectors (8500 photons/MeV), high density and atomic numbers of constituent materials which maximizes sensitivity, and relative neutron blindness which minimizes complications in data interpretation. The detectors observe primarily hard x-ray radiation emitted in a forward beamed pattern by RE when they strike first wall materials or bulk ions and neutrals in the plasma, although we also address photoneutron signals. The arrangement of the array enables time resolved location of x-ray emission and associated asymmetries which help identify instabilities and confinement properties of RE. By shielding a subset of detectors with different thicknesses of lead, and with interpretative support of the code EGSNRC, we also measure RE energy, although due to the often distributed nature of RE strike points and the forward beamed character of emitted hard x-rays, we restrict interpretation as a lower bound for RE energy.

  11. Development of SiPM-based scintillator tile detectors for a multi-layer fast neutron tracker

    Directory of Open Access Journals (Sweden)

    Jakubek J.

    2012-10-01

    Full Text Available We are developing thin tile scintillator detectors with silicon photomultiplier (SiPM readout for use in a multi-layer fast-neutron tracker. The tracker is based on interleaved Timepix and plastic scintillator layers. The thin 15 × 15 × 2 mm plastic scintillators require suitable optical readout in order to detect and measure the energy lost by energetic protons that have been recoiled by fast neutrons. Our first prototype used dual SiPMs, coupled to opposite edges of the scintillator tile using light-guides. An alternative readout geometry was designed in an effort to increase the fraction of scintillation light detected by the SiPMs. The new prototype uses a larger SiPM array to cover the entire top face of the tile. This paper details the comparative performance of the two prototype designs. A deuterium-tritium (DT fast-neutron source was used to compare the relative light collection efficiency of the two designs. A collimated UV light source was scanned across the detector face to map the uniformity. The new prototype was found to have 9.5 times better light collection efficiency over the original design. Both prototypes exhibit spatial non-uniformity in their response. Methods of correcting this non-uniformity are discussed.

  12. A novel method to calibrate DOI function of a PET detector with a dual-ended-scintillator readout.

    Science.gov (United States)

    Shao, Yiping; Yao, Rutao; Ma, Tianyu

    2008-12-01

    The detection of depth-of-interaction (DOI) is a critical detector capability to improve the PET spatial resolution uniformity across the field-of-view and will significantly enhance, in particular, small bore system performance for brain, breast, and small animal imaging. One promising technique of DOI detection is to use dual-ended-scintillator readout that uses two photon sensors to detect scintillation light from both ends of a scintillator array and estimate DOI based on the ratio of signals (similar to Anger logic). This approach needs a careful DOI function calibration to establish accurate relationship between DOI and signal ratios, and to recalibrate if the detection condition is shifted due to the drift of sensor gain, bias variations, or degraded optical coupling, etc. However, the current calibration method that uses coincident events to locate interaction positions inside a single scintillator crystal has severe drawbacks, such as complicated setup, long and repetitive measurements, and being prone to errors from various possible misalignments among the source and detector components. This method is also not practically suitable to calibrate multiple DOI functions of a crystal array. To solve these problems, a new method has been developed that requires only a uniform flood source to irradiate a crystal array without the need to locate the interaction positions, and calculates DOI functions based solely on the uniform probability distribution of interactions over DOI positions without knowledge or assumption of detector responses. Simulation and experiment have been studied to validate the new method, and the results show that the new method, with a simple setup and one single measurement, can provide consistent and accurate DOI functions for the entire array of multiple scintillator crystals. This will enable an accurate, simple, and practical DOI function calibration for the PET detectors based on the design of dual-ended-scintillator readout. In

  13. Femtosecond laser ablation of cadmium tungstate for scintillator arrays

    Science.gov (United States)

    Richards, S.; Baker, M. A.; Wilson, M. D.; Lohstroh, A.; Seller, P.

    2016-08-01

    Ultrafast pulsed laser ablation has been investigated as a technique to machine CdWO4 single crystal scintillator and segment it into small blocks with the aim of fabricating a 2D high energy X-ray imaging array. Cadmium tungstate (CdWO4) is a brittle transparent scintillator used for the detection of high energy X-rays and γ-rays. A 6 W Yb:KGW Pharos-SP pulsed laser of wavelength 1028 nm was used with a tuneable pulse duration of 10 ps to 190 fs, repetition rate of up to 600 kHz and pulse energies of up to 1 mJ was employed. The effect of varying the pulse duration, pulse energy, pulse overlap and scan pattern on the laser induced damage to the crystals was investigated. A pulse duration of ≥500 fs was found to induce substantial cracking in the material. The laser induced damage was minimised using the following operating parameters: a pulse duration of 190 fs, fluence of 15.3 J cm-2 and employing a serpentine scan pattern with a normalised pulse overlap of 0.8. The surface of the ablated surfaces was studied using scanning electron microscopy, energy dispersive X-ray spectroscopy, atomic force microscopy and X-ray photoelectron spectroscopy. Ablation products were found to contain cadmium tungstate together with different cadmium and tungsten oxides. These laser ablation products could be removed using an ammonium hydroxide treatment.

  14. Improving photoelectron counting and particle identification in scintillation detectors with Bayesian techniques

    Science.gov (United States)

    Akashi-Ronquest, M.; Amaudruz, P.-A.; Batygov, M.; Beltran, B.; Bodmer, M.; Boulay, M. G.; Broerman, B.; Buck, B.; Butcher, A.; Cai, B.; Caldwell, T.; Chen, M.; Chen, Y.; Cleveland, B.; Coakley, K.; Dering, K.; Duncan, F. A.; Formaggio, J. A.; Gagnon, R.; Gastler, D.; Giuliani, F.; Gold, M.; Golovko, V. V.; Gorel, P.; Graham, K.; Grace, E.; Guerrero, N.; Guiseppe, V.; Hallin, A. L.; Harvey, P.; Hearns, C.; Henning, R.; Hime, A.; Hofgartner, J.; Jaditz, S.; Jillings, C. J.; Kachulis, C.; Kearns, E.; Kelsey, J.; Klein, J. R.; Kuźniak, M.; LaTorre, A.; Lawson, I.; Li, O.; Lidgard, J. J.; Liimatainen, P.; Linden, S.; McFarlane, K.; McKinsey, D. N.; MacMullin, S.; Mastbaum, A.; Mathew, R.; McDonald, A. B.; Mei, D.-M.; Monroe, J.; Muir, A.; Nantais, C.; Nicolics, K.; Nikkel, J. A.; Noble, T.; O'Dwyer, E.; Olsen, K.; Orebi Gann, G. D.; Ouellet, C.; Palladino, K.; Pasuthip, P.; Perumpilly, G.; Pollmann, T.; Rau, P.; Retière, F.; Rielage, K.; Schnee, R.; Seibert, S.; Skensved, P.; Sonley, T.; Vázquez-Jáuregui, E.; Veloce, L.; Walding, J.; Wang, B.; Wang, J.; Ward, M.; Zhang, C.

    2015-05-01

    Many current and future dark matter and neutrino detectors are designed to measure scintillation light with a large array of photomultiplier tubes (PMTs). The energy resolution and particle identification capabilities of these detectors depend in part on the ability to accurately identify individual photoelectrons in PMT waveforms despite large variability in pulse amplitudes and pulse pileup. We describe a Bayesian technique that can identify the times of individual photoelectrons in a sampled PMT waveform without deconvolution, even when pileup is present. To demonstrate the technique, we apply it to the general problem of particle identification in single-phase liquid argon dark matter detectors. Using the output of the Bayesian photoelectron counting algorithm described in this paper, we construct several test statistics for rejection of backgrounds for dark matter searches in argon. Compared to simpler methods based on either observed charge or peak finding, the photoelectron counting technique improves both energy resolution and particle identification of low energy events in calibration data from the DEAP-1 detector and simulation of the larger MiniCLEAN dark matter detector.

  15. Monte Carlo simulation of a very high resolution thermal neutron detector composed of glass scintillator microfibers

    CERN Document Server

    Yushou, Song; Zhang, Xiaodong; Hayward, Jason P

    2016-01-01

    In order to develop a high spatial resolution (micron level) thermal neutron detector, a detector assembly composed of cerium doped lithium glass microfibers, each with a diameter of 1\\,$\\mu$m, is proposed, where the neutron absorption location is reconstructed from the observed charged particle products that result from neutron absorption. To suppress the cross talk of the scintillation light, each scintillating fiber is surrounded by air-filled glass capillaries with the same diameter as the fiber. This pattern is repeated to form a bulk microfiber detector. On one end, the surface of the detector is painted with a thin optical reflector to increase the light collection efficiency at the other end. Then the scintillation light emitted by any neutron interaction is transmitted to one end, magnified, and recorded by an intensified CCD camera. A simulation based on the Geant4 toolkit was developed to model this detector. All the relevant physics processes including neutron interaction, scintillation, and optic...

  16. Studies of a scintillator-bar detector for a neutron wall at an external target facility

    Institute of Scientific and Technical Information of China (English)

    YU Yu-Hong; XU Hua-Gen; XU Hu-Shan; ZHAN Wen-Long; SUN Zhi-Yu; GUO Zhong-Yan; HU Zheng-Guo; WANG Jian-Song; CHEN Jun-Ling; ZHENG Chuan

    2009-01-01

    To achieve a better time resolution of a scintillator-bar detector for a neutron wall at the external target facility of HIRFL-CSR, we have carried out a detailed study of the photomultiplier, the wrapping material and the coupling media. The timing properties of a scintillator-bar detector have been studied in detail with cosmic rays using a high and low level signal coincidence. A time resolution of 80 ps has been achieved in the center of the scintillator-bar detector.

  17. Pulse shape discrimination using EJ-299-33 plastic scintillator coupled with a Silicon Photomultiplier array

    Science.gov (United States)

    Liao, Can; Yang, Haori

    2015-07-01

    Recent developments in organic plastic scintillators capable of pulse shape discrimination (PSD) have gained much interest. Novel photon detectors, such as Silicon Photomultipliers (SiPMs), offer numerous advantages and can be used as an alternative to conventional photo multiplier tubes (PMTs) in many applications. In this work, we evaluate the PSD performance of the EJ-299-33 plastic scintillator coupled with a SiPM array. 2D PSD plots as well as the Figure of Merit (FOM) parameters are presented to demonstrate the PSD capability of EJ-299-33 using a SiPM as the light sensor. The best FOM of 0.76 was observed with a 1.0 MeVee (MeV-electron-equivalent) energy threshold, despite the high noise level of the SiPM array. A high-speed digital oscilloscope was used to acquire data, which was then processed offline in MATLAB. A performance comparison between two different PSD algorithms was carried out. The dependence of PSD quality on the sampling rate was also evaluated, stimulated by the interest to implement this setup for handheld applications where power consumption is crucial.

  18. Testing a new NIF neutron time-of-flight detector with a bibenzyl scintillator on OMEGA.

    Science.gov (United States)

    Glebov, V Yu; Forrest, C; Knauer, J P; Pruyne, A; Romanofsky, M; Sangster, T C; Shoup, M J; Stoeckl, C; Caggiano, J A; Carman, M L; Clancy, T J; Hatarik, R; McNaney, J; Zaitseva, N P

    2012-10-01

    A new neutron time-of-flight (nTOF) detector with a bibenzyl crystal as a scintillator has been designed and manufactured for the National Ignition Facility (NIF). This detector will replace a nTOF20-Spec detector with an oxygenated xylene scintillator currently operational on the NIF to improve the areal-density measurements. In addition to areal density, the bibenzyl detector will measure the D-D and D-T neutron yield and the ion temperature of indirect- and direct-drive-implosion experiments. The design of the bibenzyl detector and results of tests on the OMEGA Laser System are presented.

  19. 2D dosimetry in a proton beam with a scintillating GEM detector

    NARCIS (Netherlands)

    Seravalli, E.; De Boer, M.R.; Geurink, F.; Huizinga, J.; Kreuger, R.; Schippers, J.M.; Van Eijk, C.W.E.

    2009-01-01

    A two-dimensional position-sensitive dosimetry system based on a scintillating gas detector is being developed for pre-treatment verification of dose distributions in particle therapy. The dosimetry system consists of a chamber filled with an Ar/CF4 scintillating gas mixture, inside which two gas el

  20. Light yield measurements in a liquid scintillator detector with wavelength-shifting fibre readout

    CERN Document Server

    Doucet, M; Grégoire, G; Panman, J; Zucchelli, P

    2001-01-01

    A technique based on liquid scintillator with wavelength-shiftingfibre readout is interesting for large-mass neutrino detectors. In this paper, we present results obtained with a laboratoryprototype assembled at CERN. Mixtures made of economical chemicalcomponents were compared to commercial liquid scintillators. Thelight yield was also studied as a function of fibre diameter, fibreposition, and surface quality of the container.

  1. Detection of Extensive Cosmic Air Showers by Small Scintillation Detectors with Wavelength-Shifting Fibres

    Science.gov (United States)

    Aiola, Salvatore; La Rocca, Paola; Riggi, Francesco; Riggi, Simone

    2012-01-01

    A set of three small scintillation detectors was employed to measure correlated events due to the passage of cosmic muons originating from extensive air showers. The coincidence rate between (any) two detectors was extracted as a function of their relative distance. The difference between the arrival times in three non-aligned detectors was used…

  2. Modeling Charge Collection in Detector Arrays

    Science.gov (United States)

    Hardage, Donna (Technical Monitor); Pickel, J. C.

    2003-01-01

    A detector array charge collection model has been developed for use as an engineering tool to aid in the design of optical sensor missions for operation in the space radiation environment. This model is an enhancement of the prototype array charge collection model that was developed for the Next Generation Space Telescope (NGST) program. The primary enhancements were accounting for drift-assisted diffusion by Monte Carlo modeling techniques and implementing the modeling approaches in a windows-based code. The modeling is concerned with integrated charge collection within discrete pixels in the focal plane array (FPA), with high fidelity spatial resolution. It is applicable to all detector geometries including monolithc charge coupled devices (CCDs), Active Pixel Sensors (APS) and hybrid FPA geometries based on a detector array bump-bonded to a readout integrated circuit (ROIC).

  3. Determination of the time resolution for neutron scintillation detectors by multi-coincidence measurement

    Institute of Scientific and Technical Information of China (English)

    LI Yong-Ming; RUAN Xi-Chao; ZHOU Bin; MA Zhong-Yuan

    2011-01-01

    Based on the multi-coincidence measurement, the time resolution of three liquid scintillation detectors (BC501A) were determined strictly by solving the coincidence equations, where the influence from electronics estimated by self coincidence measurement

  4. Proton-induced radioactivity in NaI (Tl) scintillation detectors

    Science.gov (United States)

    Fishman, G. J.

    1977-01-01

    Radioactivity induced by protons in sodium iodide scintillation crystals were calculated and directly measured. These data are useful in determining trapped radiation and cosmic-ray induced, background-counting rates in spaceborne detectors.

  5. Segmented scintillation detectors with silicon photomultiplier readout for measuring antiproton annihilations

    CERN Document Server

    Sótér, A; Kobayashi, T; Barna, D; Horvath, D; Hori, M

    2014-01-01

    The Atomic Spectroscopy and Collisions Using Slow Antiprotons (ASACUSA) experiment at the Antiproton Decelerator (AD) facility of CERN constructed segmented scintillators to detect and track the charged pions which emerge from antiproton annihilations in a future superconducting radiofrequency Paul trap for antiprotons. A system of 541 cast and extruded scintillator bars were arranged in 11 detector modules which provided a spatial resolution of 17 mm. Green wavelength-shifting fibers were embedded in the scintillators, and read out by silicon photomultipliers which had a sensitive area of 1 x 1 mm^2. The photoelectron yields of various scintillator configurations were measured using a negative pion beam of momentum p ~ 1 GeV/c. Various fibers and silicon photomultipliers, fiber end terminations, and couplings between the fibers and scintillators were compared. The detectors were also tested using the antiproton beam of the AD. Nonlinear effects due to the saturation of the silicon photomultiplier were seen a...

  6. The Hybrid Energy Spectrum of TA's Middle Drum Detector and Surface Array

    CERN Document Server

    ,

    2014-01-01

    The Telescope Array experiment studies ultra high energy cosmic rays using a hybrid detector. Fluorescence telescopes measure the longitudinal development of the extensive air shower generated when a primary cosmic ray particle interacts with the atmosphere. Meanwhile, scintillator detectors measure the lateral distribution of secondary shower particles that hit the ground. The Middle Drum (MD) fluorescence telescope station consists of 14 telescopes from the High Resolution Fly's Eye (HiRes) experiment, providing a direct link back to the HiRes measurements. Using the scintillator detector data in conjunction with the telescope data improves the geometrical reconstruction of the showers significantly, and hence, provides a more accurate reconstruction of the energy of the primary particle. The Middle Drum hybrid spectrum is presented and compared to that measured by the Middle Drum station in monocular mode. Further, the hybrid data establishes a link between the Middle Drum data and the surface array. A com...

  7. Cosmic ray angular distribution employing plastic scintillation detectors and flash-ADC/FPGA-based readout systems

    International Nuclear Information System (INIS)

    It is known that secondary cosmic rays are high energetic particles which are products of shower particles, when primary cosmic rays from outer space hit the atmosphere molecules. Many studies of cosmic rays show that cosmic flux depends on the depth of atmosphere. At ground level, most secondary cosmic rays are muons, a type of charged particle, and have angular dependence. The purpose of this article was to develop the telescope with two plastic scintillation detectors to investigate the angular distribution of cosmic rays at ground level. Directions of investigation were carried out vertical, 45-degree oblique and horizontal directions with respect to earth surface, approximately from North to South. Electronic readout system was developed from Flash Analog Digital Converter (Flash-ADC) of 8 bits-250Ms/sec, and Embedded Field Programmable Gate Array (FPGA)-based trigger. LabVIEW trademark interface was written for controlling trigger system and taking data. For each direction measurement, the deposited energy spectra in the scintillators were obtained. The interest of cosmic-ray events was analyzed for counting. Angular distribution was obtained quantitatively. The experiment has been done at University of Science-HCMC. (orig.)

  8. Influence of the scintillation crystal option on the detector response of pet devices

    Directory of Open Access Journals (Sweden)

    Antić Vojislav M.

    2014-01-01

    Full Text Available Positron emission tomography is a technology that provides unique and exquisite possibilities in functional diagnostics, in the sense that it is the most efficient and most reliable method for obtaining information about biochemical activity and cellular metabolism in the body, by determining exact localization and performing semi-quantitative assessment of the distribution of a radioactive tracer. This paper compares the characteristics of recently introduced lutetium based crystals to those of conventionally used bismuth-ortho-germanate scintillators; both options are used as scintillation detectors within the positron emission tomography systems. Energy resolution and scintillation decay time of lutetium based crystals and bis-muth-ortho-germanate crystals was experimentally tested. Main scintillation detector parameters which affect the resulting detector response are considered and analyzed, since they serve as the basis for a positron emission tomography medical image. [Projekat Ministarstva nauke Republike Srbije, br. 171007

  9. How to observe 8B solar neutrinos in liquid scintillator detectors

    CERN Document Server

    Ianni, A; Villante, F L

    2016-01-01

    We show that liquid organic scintillator detectors (e.g., KamLAND and Borexino) can measure the 8B solar neutrino flux by means of the nu_e charged current interaction with the 13C nuclei naturally contained in the scintillators. The neutrino events can be identified by exploiting the time and space coincidence with the subsequent decay of the produced 13N nuclei. We perform a detailed analysis of the background in KamLAND, Borexino and in a possible liquid scintillator detector at SNOLab, showing that the 8B solar neutrino signal can be extracted with a reasonable uncertainty in a few years of data taking. KamLAND should be able to extract about 18 solar neutrino events from the already collected data. Prospects for gigantic scintillator detectors (such as LENA) are also studied.

  10. Rejection of Alpha Surface Background in Non-scintillating Bolometric Detectors: The ABSuRD Project

    Science.gov (United States)

    Biassoni, M.; Brofferio, C.; Bucci, C.; Canonica, L.; di Vacri, M. L.; Gorla, P.; Pavan, M.; Yeh, M.

    2016-08-01

    Due to their excellent energy resolution values and the vast choice of possible materials, bolometric detectors are currently widely used in the physics of rare events. A limiting aspect for bolometers rises from their inability to discriminate among radiation types or surface from bulk events. It has been demonstrated that the main limitation to sensitivity for purely bolometric detectors is represented by surface alpha contaminations, causing a continuous background that cannot be discriminated. A new scintillation-based technique for the rejection of surface alpha background in non-scintillating bolometric experiments is proposed in this work. The idea is to combine a scintillating and a high sensitivity photon detector with a non-scintillating absorber. We present results showing the possibility to reject events due to alpha decay at or nearby the surface of the crystal.

  11. Encapsulated thermopile detector array for IR microspectrometer

    OpenAIRE

    H. Wu; Emadi, A.; De Graaf, G.; Wolffenbuttel, R F

    2010-01-01

    The miniaturized IR spectrometer discussed in this paper is comprised of: slit, planar imaging diffraction grating and Thermo-Electric (TE) detector array, which is fabricated using CMOS compatible MEMS technology. The resolving power is maximized by spacing the TE elements at an as narrow as possible pitch, which is limited by processing constraints. The large aspect ratio of the TE elements implies a large cross-sectional area between adjacent elements within the array and results in a rela...

  12. Semiconductor scintillator detector for gamma radiation; Detector cintilador semicondutor para radiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Laan, F.T.V. der; Borges, V.; Zabadal, J.R.S., E-mail: ftvdl@ufrgs.br, E-mail: borges@ufrgs.br, E-mail: jorge.zabadal@ufrgs.br [Universidade Federal do Rio Grande do Sul (GENUC/DEMEC/UFRGS), Porto Alegre, RS (Brazil). Grupo de Estudos Nucleares. Departamento de Engenharia Mecanica

    2015-07-01

    Nowadays the devices employed to evaluate individual radiation exposition are based on dosimetric films and thermoluminescent crystals, whose measurements must be processed in specific transductors. Hence, these devices carry out indirect measurements. Although a new generation of detectors based on semiconductors which are employed in EPD's (Electronic Personal Dosemeters) being yet available, it high producing costs and large dimensions prevents the application in personal dosimetry. Recent research works reports the development of new detection devices based on photovoltaic PIN diodes, which were successfully employed for detecting and monitoring exposition to X rays. In this work, we step forward by coupling a 2mm anthracene scintillator NE1, which converts the high energy radiation in visible light, generating a Strong signal which allows dispensing the use of photomultipliers. A low gain high performance amplifier and a digital acquisition device are employed to measure instantaneous and cumulative doses for energies ranging from X rays to Gamma radiation up to 2 MeV. One of the most important features of the PIN diode relies in the fact that it can be employed as a detector for ionization radiation, since it requires a small energy amount for releasing electrons. Since the photodiode does not amplify the corresponding photon current, it must be coupled to a low gain amplifier. Therefore, the new sensor works as a scintillator coupled with a photodiode PIN. Preliminary experiments are being performed with this sensor, showing good results for a wide range of energy spectrum. (author)

  13. Recent progress of MPPC-based scintillation detectors in high precision X-ray and gamma-ray imaging

    Science.gov (United States)

    Kataoka, J.; Kishimoto, A.; Fujita, T.; Nishiyama, T.; Kurei, Y.; Tsujikawa, T.; Oshima, T.; Taya, T.; Iwamoto, Y.; Ogata, H.; Okochi, H.; Ohsuka, S.; Ikeda, H.; Yamamoto, S.

    2015-06-01

    The multi-pixel photon counter (MPPC) is a promising light sensor for various applications, not only in physics experiments but also in nuclear medicine, industry, and even high-energy astrophysics. In this paper, we present the current status and most recent progress of the MPPC-based scintillation detectors, such as (1) a high-precision X-ray and gamma-ray spectral image sensor, (2) next-generation PET detectors with MRI, TOF, and DOI measurement capabilities, and (3) a compact gamma camera for environmental radiation surveys. We first present a new method of fabricating a Ce:GAGG scintillator plate (1 or 2 mm thick) with ultra-fine resolution (0.2 mm/pixel), cut using a dicing saw to create 50 μm wide micro-grooves. When the plate is optically coupled with a large-area MPPC array, excellent spatial resolution of 0.48 mm (FWHM) and energy resolution of 14% (FWHM) are obtained for 122 keV gamma rays. Hence, the detector can act as a convenient "multi-color" imaging device that can potentially be used for future SPECT and photon-counting CT. We then show a prototype system for a high-resolution MPPC-based PET scanner that can realize ≃1 mm (FWHM) spatial resolution, even under a strong magnetic field of 4.7 T. We develop a front-end ASIC intended for future TOF-PET scanner with a 16-channel readout that achieves a coincidence time resolution of 489 ps (FWHM). A novel design for a module with DOI-measurement capability for gamma rays is also presented by measuring the pulse height ratio of double-sided MPPCs coupled at both ends of scintillation crystal block. Finally, we present the concept of a two-plane Compton camera consisting of Ce:GAGG scintillator arrays coupled with thin MPPC arrays. As a result of the thin and compact features of the MPPC device, the camera not only achieves a small size (14×14×15 cm3) and light weight (1.9 kg) but also excellent sensitivity, compared to the conventional PMT-based pinhole camera used in Fukushima. Finally, we briefly

  14. Assessment of a simulation software for scintillation detector

    International Nuclear Information System (INIS)

    Aim: A Monte Carlo code based on GEANT 3.21 and Linux platform has been developed and adapted to simulate gamma detectors dedicated to specific scintigraphic applications. Materials and methods: GEANT 3.21 is freely available at the CERN program library. It has been written for simulating the interactions of particles with energy > 10 keV. The energy of the gamma rays used in scintigraphic imaging never exceeds 511 keV. Interaction cross-sections for energies between 10 keV and 10 MeV and three media of interest obtained with this program have been compared with data available on the NIST web site. A gamma peroperative hand-held probe has then been simulated. Sensitivity and spatial resolution were evaluated. Results: The high standard deviation for total attenuation coefficient is 4.7% with an uncertainty around 4% given by NIST. The good results obtained have allowed us to go farther in computer programming. In the hope of integrating all the detection lines new routines have been introduced for the simulation of scintillation photons and optical effects. First simulated optical spots have a diameter of 2.5 mm (FWHM) for a 6 mm NaI(Tl) thickness and gamma rays of 140 keV. Conclusion: The code was recently improved with the implementation of a photomultiplier tube and the algorithm for the image reconstruction. In this way, the computed image can be compared with optical image obtained just before the photocathode to improve algorithm. Soon, simulation results will be tested with a mini gamma-camera prototype

  15. Fast tracking detector with fiber scintillators and a position sensitive photomultiplier

    International Nuclear Information System (INIS)

    We have studied the properties of a tracking detector composed of 32 fiber scintillators coupled to a multianode photomultiplier placed in a pion beam at TRIUMF. We measured the efficiency of the detector, as well as its tracking capabilities and double hit resolution

  16. Combined detectors of charged particles based on zinc selenide scintillators and silicon photodiodes

    CERN Document Server

    Ryzhikov, V D; Starzhinskij, N G

    2001-01-01

    combined detectors of charged particles are described based on zinc selenide (Zn Se(Te)) crystals,silicon photodiodes and charges-sensitive amplifiers. Zn Se(Te) scintillators are characterized by high alpha to beta ratio (approx 1.0), good scintillation efficiency (up to 22%),and high radiation stability (up to 100 Mrad),together with good spectral matching with silicon PIN photodiodes. The signal coming from the photodiode in the two modes (photoreceiver and semiconductor detector) differ in the amplitude values and pulse duration, which opens new possibilities for development and application of such combined detectors.

  17. Development of a Compton camera for medical applications based on silicon strip and scintillation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Krimmer, J., E-mail: j.krimmer@ipnl.in2p3.fr [Institut de Physique Nucléaire de Lyon, Université de Lyon, Université Lyon 1, CNRS/IN2P3 UMR 5822, 69622 Villeurbanne cedex (France); Ley, J.-L. [Institut de Physique Nucléaire de Lyon, Université de Lyon, Université Lyon 1, CNRS/IN2P3 UMR 5822, 69622 Villeurbanne cedex (France); Abellan, C.; Cachemiche, J.-P. [Aix-Marseille Université, CNRS/IN2P3, CPPM UMR 7346, 13288 Marseille (France); Caponetto, L.; Chen, X.; Dahoumane, M.; Dauvergne, D. [Institut de Physique Nucléaire de Lyon, Université de Lyon, Université Lyon 1, CNRS/IN2P3 UMR 5822, 69622 Villeurbanne cedex (France); Freud, N. [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA - Lyon, Université Lyon 1, Centre Léon Bérard (France); Joly, B.; Lambert, D.; Lestand, L. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, Laboratoire de Physique Corpusculaire, BP 10448, F-63000 Clermont-Ferrand (France); Létang, J.M. [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA - Lyon, Université Lyon 1, Centre Léon Bérard (France); Magne, M. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, Laboratoire de Physique Corpusculaire, BP 10448, F-63000 Clermont-Ferrand (France); and others

    2015-07-01

    A Compton camera is being developed for the purpose of ion-range monitoring during hadrontherapy via the detection of prompt-gamma rays. The system consists of a scintillating fiber beam tagging hodoscope, a stack of double sided silicon strip detectors (90×90×2 mm{sup 3}, 2×64 strips) as scatter detectors, as well as bismuth germanate (BGO) scintillation detectors (38×35×30 mm{sup 3}, 100 blocks) as absorbers. The individual components will be described, together with the status of their characterization.

  18. Discovery potential for supernova relic neutrinos with slow liquid scintillator detectors

    CERN Document Server

    Wei, Hanyu; Chen, Shaomin

    2016-01-01

    The detection of supernova relic neutrinos would provide a key support for our current understanding of stellar and cosmological evolution, and precise measurements of them would further give us an insight of the profound universe. In this paper we study the potential to detect supernova relic neutrinos using linear alkyl benzene, LAB, as a slow liquid scintillator, which features a good separation of Cherenkov and scintillation lights, thus providing a new ability in particle identification. We also address key issues of current experiments, including 1) the charged current background of atmospheric neutrinos in water Cherenkov detectors, and 2) the neutral current background of atmospheric neutrinos in typical liquid scintillator detectors. With LAB, a kiloton-scale detector, like the SNO, KamLAND, and the future Jinping neutrino detectors, with $\\mathcal{O}$(10) years of data, would have the sensitivity to discover supernova relic neutrinos, which is comparable to large-volume water Cherenkov, typical liqu...

  19. Photonic Crystals: Enhancing the Light Output of Scintillation Based Detectors

    CERN Document Server

    Knapitsch, Arno Richard

    A scintillator is a material which emits light when excited by ionizing radiation. Such materials are used in a diverse range of applications; From high energy particle physics experiments, X-ray security, to nuclear cameras or positron emission tomography. Future high-energy physics (HEP) experiments as well as next generation medical imaging applications are more and more pushing towards better scintillation characteristics. One of the problems in heavy scintillating materials is related to their high index of refraction. As a consequence, most of the scintillation light produced in the bulk material is trapped inside the crystal due to total internal reflection. The same problem also occurs with light emitting diodes (LEDs) and has for a long time been considered as a limiting factor for their overall efficiency. Recent developments in the area of nanophotonics were showing now that those limitations can be overcome by introducing a photonic crystal (PhC) slab at the outcoupling surface of the substrate. P...

  20. Subnanosecond scintillation detector for high energy cosmic rays Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The task objective is to develop a gamma ray scintillator technology with subnanosecond temporal resolution and the capability to withstand unprecedented rates and...

  1. ANTS — a simulation package for secondary scintillation Anger-camera type detector in thermal neutron imaging

    Science.gov (United States)

    Morozov, A.; Defendi, I.; Engels, R.; Fraga, F. A. F.; Fraga, M. M. F. R.; Guerard, B.; Jurkovic, M.; Kemmerling, G.; Manzin, G.; Margato, L. M. S.; Niko, H.; Pereira, L.; Petrillo, C.; Peyaud, A.; Piscitelli, F.; Raspino, D.; Rhodes, N. J.; Sacchetti, F.; Schooneveld, E. M.; Van Esch, P.; Zeitelhack, K.

    2012-08-01

    A custom and fully interactive simulation package ANTS (Anger-camera type Neutron detector: Toolkit for Simulations) has been developed to optimize the design and operation conditions of secondary scintillation Anger-camera type gaseous detectors for thermal neutron imaging. The simulation code accounts for all physical processes related to the neutron capture, energy deposition pattern, drift of electrons of the primary ionization and secondary scintillation. The photons are traced considering the wavelength-resolved refraction and transmission of the output window. Photo-detection accounts for the wavelength-resolved quantum efficiency, angular response, area sensitivity, gain and single-photoelectron spectra of the photomultipliers (PMTs). The package allows for several geometrical shapes of the PMT photocathode (round, hexagonal and square) and offers a flexible PMT array configuration: up to 100 PMTs in a custom arrangement with the square or hexagonal packing. Several read-out patterns of the PMT array are implemented. Reconstruction of the neutron capture position (projection on the plane of the light emission) is performed using the center of gravity, maximum likelihood or weighted least squares algorithm. Simulation results reproduce well the preliminary results obtained with a small-scale detector prototype. ANTS executables can be downloaded from http://coimbra.lip.pt/~andrei/.

  2. Radiation hardness of plastic scintillators for the Tile Calorimeter of the ATLAS detector

    CERN Document Server

    Jivan, Harshna; The ATLAS collaboration

    2014-01-01

    The Tile Calorimeter of the ATLAS detector, is a hadronic calorimeter responsible for detecting hadrons as well as accommodating for the missing transverse energy that result from the p-p collisions within the LHC. Plastic scintillators form an integral component of this calorimeter due to their ability to undergo prompt fluorescence when exposed to ionising particles. The scintillators employed are specifically chosen for their properties of high optical transmission and fast rise and decay time which enables efficient data capture since fast signal pulses can be generated. The main draw-back of plastic scintillators however is their susceptibility to radiation damage. The damage caused by radiation exposure reduces the scintillation light yield and introduces an error into the time-of flight data acquired. During Run 1 of the LHC data taking period, plastic scintillators employed within the GAP region between the Tile Calorimeter’s central and extended barrels sustained a significant amount of damage. Wit...

  3. A systematic characterization of the low-energy photon response of plastic scintillation detectors.

    Science.gov (United States)

    Boivin, Jonathan; Beddar, Sam; Bonde, Chris; Schmidt, Daniel; Culberson, Wesley; Guillemette, Maxime; Beaulieu, Luc

    2016-08-01

    To characterize the low energy behavior of scintillating materials used in plastic scintillation detectors (PSDs), 3 PSDs were developed using polystyrene-based scintillating materials emitting in different wavelengths. These detectors were exposed to National Institute of Standards and Technology (NIST)-matched low-energy beams ranging from 20 kVp to 250 kVp, and to (137)Cs and (60)Co beams. The dose in polystyrene was compared to the dose in air measured by NIST-calibrated ionization chambers at the same location. Analysis of every beam quality spectrum was used to extract the beam parameters and the effective mass energy-absorption coefficient. Monte Carlo simulations were also performed to calculate the energy absorbed in the scintillators' volume. The scintillators' expected response was then compared to the experimental measurements and an energy-dependent correction factor was identified to account for low-energy quenching in the scintillators. The empirical Birks model was then compared to these values to verify its validity for low-energy electrons. The clear optical fiber response was below 0.2% of the scintillator's light for x-ray beams, indicating that a negligible amount of fluorescence contamination was produced. However, for higher-energy beams ((137)Cs and (60)Co), the scintillators' response was corrected for the Cerenkov stem effect. The scintillators' response increased by a factor of approximately 4 from a 20 kVp to a (60)Co beam. The decrease in sensitivity from ionization quenching reached a local minimum of about [Formula: see text] between 40 keV and 60 keV x-ray beam mean energy, but dropped by 20% for very low-energy (13 keV) beams. The Birks model may be used to fit the experimental data, but it must take into account the energy dependence of the kB quenching parameter. A detailed comprehension of intrinsic scintillator response is essential for proper calibration of PSD dosimeters for radiology.

  4. Performance of SEM scintillation detector evaluated by modulation transfer function and detective quantum efficiency function.

    Science.gov (United States)

    Bok, Jan; Schauer, Petr

    2014-01-01

    In the paper, the SEM detector is evaluated by the modulation transfer function (MTF) which expresses the detector's influence on the SEM image contrast. This is a novel approach, since the MTF was used previously to describe only the area imaging detectors, or whole imaging systems. The measurement technique and calculation of the MTF for the SEM detector are presented. In addition, the measurement and calculation of the detective quantum efficiency (DQE) as a function of the spatial frequency for the SEM detector are described. In this technique, the time modulated e-beam is used in order to create well-defined input signal for the detector. The MTF and DQE measurements are demonstrated on the Everhart-Thornley scintillation detector. This detector was alternated using the YAG:Ce, YAP:Ce, and CRY18 single-crystal scintillators. The presented MTF and DQE characteristics show good imaging properties of the detectors with the YAP:Ce or CRY18 scintillator, especially for a specific type of the e-beam scan. The results demonstrate the great benefit of the description of SEM detectors using the MTF and DQE. In addition, point-by-point and continual-sweep e-beam scans in SEM were discussed and their influence on the image quality was revealed using the MTF.

  5. Performance of SEM scintillation detector evaluated by modulation transfer function and detective quantum efficiency function.

    Science.gov (United States)

    Bok, Jan; Schauer, Petr

    2014-01-01

    In the paper, the SEM detector is evaluated by the modulation transfer function (MTF) which expresses the detector's influence on the SEM image contrast. This is a novel approach, since the MTF was used previously to describe only the area imaging detectors, or whole imaging systems. The measurement technique and calculation of the MTF for the SEM detector are presented. In addition, the measurement and calculation of the detective quantum efficiency (DQE) as a function of the spatial frequency for the SEM detector are described. In this technique, the time modulated e-beam is used in order to create well-defined input signal for the detector. The MTF and DQE measurements are demonstrated on the Everhart-Thornley scintillation detector. This detector was alternated using the YAG:Ce, YAP:Ce, and CRY18 single-crystal scintillators. The presented MTF and DQE characteristics show good imaging properties of the detectors with the YAP:Ce or CRY18 scintillator, especially for a specific type of the e-beam scan. The results demonstrate the great benefit of the description of SEM detectors using the MTF and DQE. In addition, point-by-point and continual-sweep e-beam scans in SEM were discussed and their influence on the image quality was revealed using the MTF. PMID:24323770

  6. Combinatorial Screening of Advanced Scintillators for High Resolution X-ray Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Shifan; Tao, Dejie; Lynch, Michael; Yuan, Xianglong; Li, Yiqun

    2008-05-12

    The lack of efficient scintillators is a major problem for developing powerful x-ray detectors that are widely used in homeland security, industrial and scientific research. Intematix has developed and applied a high throughput screening process and corresponding crystal growth technology to significantly speed up the discovery process for new efficient scintillators. As a result, Intematix has invented and fabricated three new scintillators both in powder and bulk forms, which possess promising properties such as better radiation hardness and better matching for silicon diode.

  7. Combination of a silicon photodiode and a scintillator as a dose rate detector

    Energy Technology Data Exchange (ETDEWEB)

    Gilar, O. (Tesla, Premysleni (Czechoslovakia). Vyzkumny Ustav Pristroju Jaderne Techniky); Petr, I. (Ceske Vysoke Uceni Technicke, Prague (Czechoslovakia). Fakulta Jaderna a Fysikalne Inzenyrska)

    1985-03-16

    The combination of a silicon photodiode adjacent to a CsI(Tl) scintillator as a detector of ..gamma..-rays is described. Theoretical conclusions are verified by an experiment and prove that the photodiode absorption spectrum as well as the quantum efficiency can be varied by an appropriate photodiode technology. The contribution of scintillation photons emitted by the CsI(Tl) scintillator in the photon field can enhance the total photocurrent more than an order of magnitude compared to the current response of the photodiode alone, placed in a photon field of equal exposure rate.

  8. POSSuMUS. A position sensitive scintillating muon SiPM detector

    International Nuclear Information System (INIS)

    The development of a modular designed large scale scintillation detector with a two-dimensional position sensitivity is presented in this thesis. This novel POsition Sensitive Scintillating MUon SiPM Detector is named POSSuMUS. The POSSuMUS detector is capable to determine the particle's position in two space dimensions with a fast trigger capability. Each module is constructed from two trapezoidal shaped plastic scintillators to form one rectangular shaped detector module. Both trapezoids are optically insulated against each other. In both trapezoids the scintillation light is collected by plastic fibers and guided towards silicon photomultipliers (SiPMs). SiPMs are light sensors which are capable to detect even smallest amounts of light. By combining several detector modules, position sensitive areas from 100 cm2 to few m2 are achievable with few readout channels. Therefore, POSSuMUS provides a cost effective detector concept. The position sensitivity along the trapezoidal geometry of one detector module is achieved by the path length dependent amount of detected light for crossing particles. The ratio of the light yields in both trapezoids is calculated. This value corresponds to the position of the particle traversing the detector. A spatial resolution in the order of several mm is foreseen. The position sensitivity along the scintillator module is determined by the propagation time of light to the SiPMs located on opposite sides of the detector. A spatial resolution of few cm is expected for this direction. The POSSuMUS detector is applicable as large area trigger detector with a two dimensional position information of crossing particles. This is suitable in detector tests of large area precesion detectors or for measuring the small angle scattering of cosmic muons. At the beginning of this thesis, the determination of important SiPM characteristics like the breakdown voltage is presented. In the course of this work the detector principle is proven by the

  9. Scintillation neutron detectors based on solid-state photomultipliers and lightguides

    Energy Technology Data Exchange (ETDEWEB)

    Litvin, V. S., E-mail: vlitvin@inr.ru; Marin, V. N.; Karaevsky, S. K.; Trunov, D. N.; Axenov, S. N.; Stolyarov, A. A.; Sadykov, R. A. [Russian Academy of Sciences, Institute for Nuclear Research (Russian Federation)

    2016-01-15

    Neutron detectors based on scintillation screens ZnS(Ag)/LiF and solid-state photomultipliers have been developed. Lightguides are used to collect light. The application of a coincidence scheme provides a low dark count and a neutron detection efficiency as high as 70%. A scheme of x-y neutron detector based on wavelength shifting fibers is also proposed. Tests of the proposed versions of detectors in a neutron beam have shown their efficiency.

  10. Scintillation neutron detectors based on solid-state photomultipliers and lightguides

    International Nuclear Information System (INIS)

    Neutron detectors based on scintillation screens ZnS(Ag)/LiF and solid-state photomultipliers have been developed. Lightguides are used to collect light. The application of a coincidence scheme provides a low dark count and a neutron detection efficiency as high as 70%. A scheme of x-y neutron detector based on wavelength shifting fibers is also proposed. Tests of the proposed versions of detectors in a neutron beam have shown their efficiency

  11. SU-C-201-01: Investigation of the Effects of Scintillator Surface Treatment On Light Output Measurements with SiPM Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Valenciaga, Y; Prout, D; Chatziioannou, A [University of California, Los Angeles (UCLA) (United States)

    2015-06-15

    Purpose: To examine the effect of different scintillator surface treatments (BGO crystals) on the fraction of scintillation photons that exit the crystal and reach the photodetector (SiPM). Methods: Positron Emission Tomography is based on the detection of light that exits scintillator crystals, after annihilation photons deposit energy inside these crystals. A considerable fraction of the scintillation light gets trapped or absorbed after going through multiple internal reflections on the interfaces surrounding the crystals. BGO scintillator crystals generate considerably less scintillation light than crystals made of LSO and its variants. Therefore, it is crucial that the small amount of light produced by BGO exits towards the light detector. The surface treatment of scintillator crystals is among the factors affecting the ability of scintillation light to reach the detectors. In this study, we analyze the effect of different crystal surface treatments on the fraction of scintillation light that is detected by the solid state photodetector (SiPM), once energy is deposited inside a BGO crystal. Simulations were performed by a Monte Carlo based software named GATE, and validated by measurements from individual BGO crystals coupled to Philips digital-SiPM sensor (DPC-3200). Results: The results showed an increment in light collection of about 4 percent when only the exit face of the BGO crystal, is unpolished; compared to when all the faces are polished. However, leaving several faces unpolished caused a reduction of at least 10 percent of light output when the interaction occurs as far from the exit face of the crystal as possible compared to when it occurs very close to the exit face. Conclusion: This work demonstrates the advantages on light collection from leaving unpolished the exit face of BGO crystals. The configuration with best light output will be used to obtain flood images from BGO crystal arrays coupled to SiPM sensors.

  12. Spallation reactions studied with 4-detector arrays

    Indian Academy of Sciences (India)

    J Galin

    2001-07-01

    Recently there has been a renewed interest in the study of spallation reactions in basic nuclear physics as well as in potential applications. Spallation reactions induced by light projectiles (protons, antiprotons, pions, etc.) in the GeV range allow the formation of hot nuclei which do not suffer the collective excitations (compression, rotation, deformation) unavoidable when using massive projectiles. Such nuclei provide an ideal testbench for probing their decay as a function of excitation energy. In these investigations, 4-detector arrays for charged particles and neutrons play a major role in the event-by-event sorting according to the excitation energy of the nucleus. Spallation reactions induced on heavy nuclei allow the conversion of the incident GeV proton into several tens of evaporated neutrons. The neutron production in thick targets has been investigated in great detail thanks to the use of high efficiency neutron detector arrays. When scattered on samples of inert or biological materials, these neutrons can be used to study details of the material structure. They could also be utilized for the transmutation of long-lived nuclear wastes or for the feeding of sub-critical nuclear reactors. The role of different types of multi-detector arrays is highlighted in this paper. Several references are also given for different uses of high efficiency neutron detectors in other contexts.

  13. Time resolution in scintillator based detectors for positron emission tomography

    International Nuclear Information System (INIS)

    In the domain of medical photon detectors L(Y)SO scintillators are used for positron emission tomography (PET). The interest for time of flight (TOF) in PET is increasing since measurements have shown that new crystals like L(Y)SO coupled to state of the art photodetectors, e.g. silicon photomultipliers (SiPM), can reach coincidence time resolutions (CTRs) of far below 500ps FWHM. To achieve these goals it is important to study the processe in the whole detection chain, i.e. the high energy particle or gamma interaction in the crystal, the scintillation process itself, the light propagation in the crystal with the light transfer to the photodetector, and the electronic readout. In this thesis time resolution measurements for a PET like system are performed in a coincidence setup utilizing the ultra fast amplifier discriminator NINO. We found that the time-over-threshold energy information provided by NINO shows a degradation in energy resolution for higher SiPM bias voltages. This is a consequence of the increasing dark count rate (DCR) of the SiPM with higher bias voltages together with the exponential decay of the signal. To overcome this problem and to operate the SiPM at its optimum voltage in terms of timing we developed a new electronic board that employs NINO only as a low noise leading edge discriminator together with an analog amplifier which delivers the energy information. With this new electronic board we indeed improved the measured CTR by about 15%. To study the limits of time resolution in more depth we measured the CTR with 2x2x3mm3 LSO:Ce codoped 0.4%Ca crystals coupled to commercially available SiPMs (Hamamatsu S10931-50P MPPC) and achieved a CTR of 108±5ps FWHM at an energy of 511keV. We determined the influence of the data acquisition system and the electronics on the CTR to be 27±2ps FWHM and thus negligible. To quantitatively understand the measured values, we developed a Monte Carlo simulation tool in MATLAB that incorporates the timing

  14. Scintillation characteristics of phosphich-detector for detection of beta- and gamma-radiations

    CERN Document Server

    Ananenko, A A; Gavrilyuk, V

    2002-01-01

    The results of the study on the influence of individual peculiarities of the compound scintillation detector structure on the value and stability of the light yield by the gamma- and beta-radiation combined registration are presented. The phosphich detector is manufactured from the sodium iodide monocrystal, activated by thallium, and the scintillation plastic on the polystyrol basis. The comparison of the experimental results with the mathematical modeling data revealed certain regularities of the process of forming the phosphich detector light signal. The recommendations are worked out by means whereof the following characteristics of the scintillation unit: the light yield and its stability, amplitude resolution and the peak-to-valley ratio by the gamma- and beta-radiation registration were improved

  15. Study of neutron-gamma pulse shape discrimination algorithms for scintillation detector

    International Nuclear Information System (INIS)

    Differentiating pulse of neutron and gamma is one of the important problem in measurements neutron spectrometry using the scintillation detector. This paper presents the research results of neutron-gamma pulse shape discrimination for an NE213 liquid scintillation detectors. From the data simulation software MatLab, four algorithms neutron-gamma pulse shape discrimination were studied. The results obtained show that method for rise-time discrimination has quality factor (Figure of-Merits: FOM=1.09), pulsed gradient analysis method (FOM=0.66), charge comparison method (FOM =2.21), and correlation pattern method (FOM = 1.97). This result is the basis for building systems used measurements neutron by scintillation detectors. (author)

  16. Compensational scintillation detector with a flat energy response for flash X-ray measurements

    Science.gov (United States)

    Chen, Liang; Ouyang, Xiaoping; Liu, Bin; Liu, Jinliang; Quan, Lin; Zhang, Zhongbing

    2013-01-01

    To measure the intensity of flash X-ray sources directly, a novel scintillation detector with a fast time response and flat energy response is developed by combining film scintillators of doped ZnO crystal and fast organic scintillator together. Through compensation design, the dual-scintillator detector (DSD) achieved a flat energy response to X-rays from tens of keV to several MeV, and sub-nanosecond time response by coupling to ultrafast photo-electronic devices. A prototype detector was fabricated according to the theoretical design; it employed ZnO:In and EJ228 with thicknesses of 0.3 mm and 0.1 mm, respectively. The energy response of this detector was tested on monoenergetic X-ray and γ-ray sources. The detector performs very well with a sensitivity fluctuation below 5% for 8 discrete energy points within the 40-250 keV energy region and for other energies of 662 keV and 1.25 MeV as well, showing good accordance with the theoretical design. Additionally, the detector works properly for the application to the flash X-ray radiation field absolute intensity measurement. This DSD may be very useful for the diagnosis of time-resolved dynamic physical processes of flash X-ray sources without knowing the exact energy spectrum.

  17. A Novel Particle Detector: Quantum Dot Doped Liquid Scintillator

    Science.gov (United States)

    Winslow, Lindley; Conrad, Janet; Jerry, Ruel

    2010-02-01

    Quantum dots are semiconducting nanocrystals. When excited by light shorter then their characteristic wavelength, they re-emit in a narrow band around this wavelength. The size of the quantum is proportional to the characteristic wavelength so they can be tuned for many applications. CdS quantum dots are made in wavelengths from 360nm to 460nm, a perfect range for the sensitivity of photo-multiplier tubes. The synthesis of quantum dots automatically leaves them in toluene, a good organic scintillator and Cd is a particularly interesting material as it has one of the highest thermal neutron cross sections and has several neutrinoless double beta decay and double electron capture isotopes. The performance of quantum dot loaded scintillator compared to standard scintillators is measured and some unique properties presented. )

  18. Investigation of Very Fast Light Detectors: Silicon Photomultiplier and Micro PMT for a Cosmic Ray Array

    Science.gov (United States)

    Cervantes, Omar; Reyes, Liliana; Hooks, Tyler; Perez, Luis; Ritt, Stefan

    2016-03-01

    To construct a cosmic detector array using 4 scintillation detectors, we investigated 2 recent light sensor technologies from Hamamatsu, as possible readout detectors. First, we investigated several homemade versions of the multipixel photon counter (MPPC) light sensors. These detectors were either biased with internal or external high voltage power supplies. We made extensive measurements to confirm for the coincidence of the MPPC devices. Each sensor is coupled to a wavelength shifting fiber (WSF) that is embedded along a plastic scintillator sheet (30cmx60cmx1/4''). Using energetic cosmic rays, we evaluated several of these homemade detector modules placed above one another in a light proof enclosure. Next, we assembled 2 miniaturized micro photomultiplier (micro PMT), a device recently marketed by Hamamatsu. These sensors showed very fast response times. With 3 WSF embedded in scintillator sheets, we performed coincidence experiments. The detector waveforms were captured using the 5GS/sec domino ring sampler, the DRS4 and our workflow using the CERN PAW package and data analysis results would be presented. Title V Grant.

  19. PoGOLino: A scintillator-based balloon-borne neutron detector

    Energy Technology Data Exchange (ETDEWEB)

    Kole, Merlin, E-mail: merlin@particle.kth.se [KTH Royal Institute of Technology, Department of Physics, 106 91 Stockholm (Sweden); The Oskar Klein Centre for Cosmoparticle Physics, AlbaNova University Centre, 106 91 Stockholm (Sweden); Chauvin, Maxime [KTH Royal Institute of Technology, Department of Physics, 106 91 Stockholm (Sweden); The Oskar Klein Centre for Cosmoparticle Physics, AlbaNova University Centre, 106 91 Stockholm (Sweden); Fukazawa, Yasushi [Department of Physical Science, Hiroshima University, Hiroshima 739-8526 (Japan); Fukuda, Kentaro; Ishizu, Sumito [Tokuyama Corporation, Shunan, Yamaguchi (Japan); Jackson, Miranda [KTH Royal Institute of Technology, Department of Physics, 106 91 Stockholm (Sweden); The Oskar Klein Centre for Cosmoparticle Physics, AlbaNova University Centre, 106 91 Stockholm (Sweden); Kamae, Tune [University of Tokyo, Department of Physics, 113-0033 Tokyo (Japan); Kawaguchi, Noriaki [Tokuyama Corporation, Shunan, Yamaguchi (Japan); Kawano, Takafumi [Department of Physical Science, Hiroshima University, Hiroshima 739-8526 (Japan); Kiss, Mózsi; Moretti, Elena; Pearce, Mark; Rydström, Stefan [KTH Royal Institute of Technology, Department of Physics, 106 91 Stockholm (Sweden); The Oskar Klein Centre for Cosmoparticle Physics, AlbaNova University Centre, 106 91 Stockholm (Sweden); Takahashi, Hiromitsu [Department of Physical Science, Hiroshima University, Hiroshima 739-8526 (Japan); Yanagida, Takayuki [Kyushu Institute of Technology, Kitakyushu, Fukuoka (Japan)

    2015-01-11

    PoGOLino is a balloon-borne scintillator-based experiment developed to study the largely unexplored high altitude neutron environment at high geomagnetic latitudes. The instrument comprises two detectors that make use of LiCAF, a novel neutron sensitive scintillator, sandwiched by BGO crystals for background reduction. The experiment was launched on March 20th 2013 from the Esrange Space Centre, Northern Sweden (geomagnetic latitude of 65°), for a three hour flight during which the instrument took data up to an altitude of 30.9 km. The detector design and ground calibration results are presented together with the measurement results from the balloon flight.

  20. Development of new scintillating fiber detectors for high energy physics applications

    International Nuclear Information System (INIS)

    We have been developing new scintillating fiber detectors for colliding beam and fixed target applications. In this paper, we present initial results from a development study of high refractive index, liquid scintillator, and the incorporation of these liquids into glass capillaries. Advantages of liquid in-capillary fiber detectors include: high efficiency and fast decay; the potential for high-resolution tracking as light emission is expected to be local to the deposited ionization in liquids containing single solutes; the potential for good radiation resistance and replaceability. 13 refs., 2 figs., 3 tabs

  1. Development of new scintillating fiber detectors for high energy physics applications

    International Nuclear Information System (INIS)

    The authors have been developing new scintillating fiber detectors for colliding beam and fixed target applications. In this paper, they present initial results from a developmental study of high refractive index, liquid scintillators, and the incorporation of these liquids into glass capillaries. Advantages of liquid-in-capillary fiber detectors include: high efficiency and fast decay; the potential for high-resolution tracking as light emission is expected to be local to the deposited ionization in liquids containing single solutes; the potential for good radiation resistance; and replaceability

  2. PoGOLino: a scintillator-based balloon-borne neutron detector

    CERN Document Server

    Kole, Merlin; Fukazawa, Yasushi; Fukuda, Kentaro; Ishizu, Sumito; Jackson, Miranda; Kamae, Tune; Kawaguchi, Noriaki; Kawano, Takafumi; Kiss, Mozsi; Moretti, Elena; Pearce, Mark; Rydström, Stefan; Takahashi, Hiromitsu; Yanagida, Takayuki

    2014-01-01

    PoGOLino is a balloon-borne scintillator-based experiment developed to study the largely unexplored high altitude neutron environment at high geomagnetic latitudes. The instrument comprises two detectors that make use of LiCAF, a novel neutron sensitive scintillator, sandwiched by BGO crystals for background reduction. The experiment was launched on March 20th 2013 from the Esrange Space Centre, Northern Sweden (geomagnetic latitude of $65^\\circ$), for a three hour flight during which the instrument took data up to an altitude of 30.9 km. The detector design and ground calibration results are presented together with the measurement results from the balloon flight.

  3. Investigation of the PGNAA using the LaBr3 scintillation detector.

    Science.gov (United States)

    Favalli, A; Mehner, H-C; Ciriello, V; Pedersen, B

    2010-01-01

    The Joint Research Centre of the European Commission develops instrumentation for detection of hazardous materials. In relation to this a new experimental facility was constructed for research into methods applying the detection of characteristic gamma rays subsequent to neutron irradiation. This includes the detection of prompt gamma rays from neutron inelastic scattering and neutron capture. For this purpose the device employs LaBr(3) scintillation detectors. The paper investigates the applicability of the LaBr(3) scintillation detector to PGNAA. PMID:19884018

  4. Investigation of the PGNAA using the LaBr{sub 3} scintillation detector

    Energy Technology Data Exchange (ETDEWEB)

    Favalli, A. [European Commission, Joint Research Centre, Institute for the Protection and Security of Citizen, TP800, Via E. Fermi, 21027 Ispra (Italy)], E-mail: andrea.dr.favalli@gmail.com; Mehner, H-C.; Ciriello, V.; Pedersen, B. [European Commission, Joint Research Centre, Institute for the Protection and Security of Citizen, TP800, Via E. Fermi, 21027 Ispra (Italy)

    2010-04-15

    The Joint Research Centre of the European Commission develops instrumentation for detection of hazardous materials. In relation to this a new experimental facility was constructed for research into methods applying the detection of characteristic gamma rays subsequent to neutron irradiation. This includes the detection of prompt gamma rays from neutron inelastic scattering and neutron capture. For this purpose the device employs LaBr{sub 3} scintillation detectors. The paper investigates the applicability of the LaBr{sub 3} scintillation detector to PGNAA.

  5. A position-sensitive scintillation detector for two-dimensional angular correlation of annihilation radiation using metal-package position-sensitive photomultiplier tubes

    CERN Document Server

    Inoue, K; Saito, H; Nagashima, Y; Hyodo, T; Muramatsu, S; Nagai, S

    1999-01-01

    We have constructed and tested a prototype of a new position sensitive gamma-ray detector which consists of an array of 2.6x2.6x18 mm sup 3 BGO scintillator blocks, a light guide, and four metal-package position-sensitive photomultiplier tubes (R5900-00-C8) recently developed by Hamamatsu Photonics Co. Ltd. Scalability of the detector of this type makes it possible to construct a larger detector using many PS-PMTs, which will be useful for the two-dimensional angular correlation of annihilation radiation apparatus.

  6. Inferential physical measurements using detectors and detector arrays

    Science.gov (United States)

    Abbott, F.; Burhardt, K. K.; Waltz, F. M.

    1980-01-01

    Some uses of photodiode detector arrays for on-line inferential measurement of process parameters are described in this paper. Optical considerations involving these arrays are discussed. High resolution camera lenses are not necessarily best in these applications since different lens design considerations apply when discrete arrays are used. Serious linearity and repeatability problems that were encountered with some commercially available solid state camera systems are discussed. The requirement of modest system cost, coupled with the need for high speed on-line analysis, place stringent restrictions on the type and amount of computer analysis that can be carried out. A set of recognition algorithms which have worked well in the initial applications are described. Some of the remaining problems, and possible approaches to them, are presented.

  7. First-principles Electronic Structure Calculations for Scintillation Phosphor Nuclear Detector Materials

    Science.gov (United States)

    Canning, Andrew

    2013-03-01

    Inorganic scintillation phosphors (scintillators) are extensively employed as radiation detector materials in many fields of applied and fundamental research such as medical imaging, high energy physics, astrophysics, oil exploration and nuclear materials detection for homeland security and other applications. The ideal scintillator for gamma ray detection must have exceptional performance in terms of stopping power, luminosity, proportionality, speed, and cost. Recently, trivalent lanthanide dopants such as Ce and Eu have received greater attention for fast and bright scintillators as the optical 5d to 4f transition is relatively fast. However, crystal growth and production costs remain challenging for these new materials so there is still a need for new higher performing scintillators that meet the needs of the different application areas. First principles calculations can provide a useful insight into the chemical and electronic properties of such materials and hence can aid in the search for better new scintillators. In the past there has been little first-principles work done on scintillator materials in part because it means modeling f electrons in lanthanides as well as complex excited state and scattering processes. In this talk I will give an overview of the scintillation process and show how first-principles calculations can be applied to such systems to gain a better understanding of the physics involved. I will also present work on a high-throughput first principles approach to select new scintillator materials for fabrication as well as present more detailed calculations to study trapping process etc. that can limit their brightness. This work in collaboration with experimental groups has lead to the discovery of some new bright scintillators. Work supported by the U.S. Department of Homeland Security and carried out under U.S. Department of Energy Contract no. DE-AC02-05CH11231 at Lawrence Berkeley National Laboratory.

  8. Dosimetry in clinical static magnetic fields using plastic scintillation detectors

    DEFF Research Database (Denmark)

    Stefanowicz, S.; Latzel, H.; Lindvold, Lars René;

    2013-01-01

    . In conclusion, we found some deviations up to 7% of the supposed signal. Although the scintillators are of much denser material, we measured the same behavior in signal as in (Meijsing et al., 2009) for a Farmer ionization chamber or as in (Raaijmakers et al., 2007) for films described which indicates radiation...

  9. Test of TOF Scintillator Counters for ALICE Detector

    CERN Document Server

    Semenov, P; Malakhov, A; Melkumov, G L

    1996-01-01

    The manufactured counters of the fast response scintillators with the photomultipliers valid for operation in the magnetic field environment is being considered among the options for the time-of-flight (TOF) measurements as a particle identification tool for the ALICE experiment. Here we discuss how the tests of such counters have been implemented on the particle beam in respect to the time resolution.

  10. Data analysis in solar neutrinos liquid-scintillator detectors

    Energy Technology Data Exchange (ETDEWEB)

    Testera, G. [INFN, Genova (Italy)

    2016-04-15

    This paper focuses on the description of some of the methods developed to extract the solar neutrino signal from the background by the two running experiments (Borexino and Kamland) based on the use of a large volume of liquid scintillator. (orig.)

  11. System qualification of Digital Detector Array (DDA)

    Energy Technology Data Exchange (ETDEWEB)

    Azeredo, Soraia R.; Oliveira, Davi F.; Nascimento, Joseilson R.; Lopes, Ricardo T., E-mail: soraia@lin.ufrj.br [Coordenacao dos Programas de Pos-Graducao em Engenharia (LIN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Lab. de Instrumentacao Nuclear

    2013-07-01

    Digital Detector Arrays (DDAs) should be characterized to establish the operating conditions of the system prior to perform a NDT (Nondestructive Testing). The image quality in digital radiography depends on the exposure conditions and the properties of the digital detectors. Quantitative definitions of DDA characterization parameters are important to discussions about achieved image quality of a particular type of DDA and also contribute to quantitative comparison of DDAs so that an appropriate digital detector is selected to meet NDT requirements. Evaluations of DDA factors were performed as defined by the standard practice for manufacturing characterization of DDAs, ASTM E2597-07. The evaluations provided quantitative results of some characteristic parameters. The factors evaluated were: basic spatial resolution, achievable contrast sensitivity, specific material thickness range and image lag. The results of measurements of characterization parameters are presented and related with the definitions in ASTM E2597-07. (author)

  12. Advanced Scintillator Detector Concept (ASDC): A Concept Paper on the Physics Potential of Water-Based Liquid Scintillator

    CERN Document Server

    Alonso, J R; Bergevin, M; Bernstein, A; Bignell, L; Blucher, E; Calaprice, F; Conrad, J M; Descamps, F B; Diwan, M V; Dwyer, D A; Dye, S T; Elagin, A; Feng, P; Grant, C; Grullon, S; Hans, S; Jaffe, D E; Kettell, S H; Klein, J R; Lande, K; Learned, J G; Luk, K B; Maricic, J; Marleau, P; Mastbaum, A; McDonough, W F; Oberauer, L; Gann, G D Orebi; Rosero, R; Rountree, S D; Sanchez, M C; Shaevitz, M H; Shokair, T M; Smy, M B; Strait, M; Svoboda, R; Tolich, N; Vagins, M R; van Bibber, K A; Viren, B; Vogelaar, R B; Wetstein, M J; Winslow, L; Wonsak, B; Worcester, E T; Wurm, M; Yeh, M; Zhang, C

    2014-01-01

    The recent development of Water-based Liquid Scintillator (WbLS), and the concurrent development of high-efficiency and high-precision-timing light sensors, has opened up the possibility for a new kind of large-scale detector capable of a very broad program of physics. The program would include determination of the neutrino mass hierarchy and observation of CP violation with long-baseline neutrinos, searches for proton decay, ultra-precise solar neutrino measurements, geo- and supernova neutrinos including diff?use supernova antineutrinos, and neutrinoless double beta decay. We outline here the basic requirements of the Advanced Scintillation Detector Concept (ASDC), which combines the use of WbLS, doping with a number of potential isotopes for a range of physics goals, high efficiency and ultra-fast timing photosensors, and a deep underground location. We are considering such a detector at the Long Baseline Neutrino Facility (LBNF) far site, where the ASDC could operate in conjunction with the liquid argon t...

  13. The scintillating fiber focal plane detector for the use of Kaos as a double arm spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Ayerbe Gayoso, Carlos Antonio

    2012-05-25

    The upgrade of the Mainz Mikrotron (MAMI) electron accelerator facility in 2007 which raised the beam energy up to 1.5 GeV, gives the opportunity to study strangeness production channels through electromagnetic process. The Kaon Spectrometer (KAOS) managed by the A1 Collaboration, enables the efficient detection of the kaons associated with strangeness electroproduction. Used as a single arm spectrometer, it can be combined with the existing high-resolution spectrometers for exclusive measurements in the kinematic domain accessible to them. For studying hypernuclear production in the {sup A}Z(e,e'K{sup +}){sup A}{sub {lambda}}(Z-1) reaction, the detection of electrons at very forward angles is needed. Therefore, the use of KAOS as a double-arm spectrometer for detection of kaons and the electrons at the same time is mandatory. Thus, the electron arm should be provided with a new detector package, with high counting rate capability and high granularity for a good spatial resolution. To this end, a new state-of-the-art scintillating fiber hodoscope has been developed as an electron detector. The hodoscope is made of two planes with a total of 18432 scintillating double-clad fibers of 0.83 mm diameter. Each plane is formed by 72 modules. Each module is formed from a 60 slanted multi-layer bundle, where 4 fibers of a tilted column are connected to a common read out. The read-out is made with 32 channels of linear array multianode photomultipliers. Signal processing makes use of newly developed double-threshold discriminators. The discriminated signal is sent in parallel to dead-time free time-to-digital modules and to logic modules for triggering purposes. Two fiber modules were tested with a carbon beam at GSI, showing a time resolution of {proportional_to}220 ps (FWHM) and a position resolution of {proportional_to}270 {mu}m (FWHM) with a detection efficiency {epsilon}>99%. The characterization of the spectrometer arm has been achieved through simulations

  14. The scintillating fiber focal plane detector for the use of Kaos as a double arm spectrometer

    International Nuclear Information System (INIS)

    The upgrade of the Mainz Mikrotron (MAMI) electron accelerator facility in 2007 which raised the beam energy up to 1.5 GeV, gives the opportunity to study strangeness production channels through electromagnetic process. The Kaon Spectrometer (KAOS) managed by the A1 Collaboration, enables the efficient detection of the kaons associated with strangeness electroproduction. Used as a single arm spectrometer, it can be combined with the existing high-resolution spectrometers for exclusive measurements in the kinematic domain accessible to them. For studying hypernuclear production in the AZ(e,e'K+)AΛ(Z-1) reaction, the detection of electrons at very forward angles is needed. Therefore, the use of KAOS as a double-arm spectrometer for detection of kaons and the electrons at the same time is mandatory. Thus, the electron arm should be provided with a new detector package, with high counting rate capability and high granularity for a good spatial resolution. To this end, a new state-of-the-art scintillating fiber hodoscope has been developed as an electron detector. The hodoscope is made of two planes with a total of 18432 scintillating double-clad fibers of 0.83 mm diameter. Each plane is formed by 72 modules. Each module is formed from a 60 slanted multi-layer bundle, where 4 fibers of a tilted column are connected to a common read out. The read-out is made with 32 channels of linear array multianode photomultipliers. Signal processing makes use of newly developed double-threshold discriminators. The discriminated signal is sent in parallel to dead-time free time-to-digital modules and to logic modules for triggering purposes. Two fiber modules were tested with a carbon beam at GSI, showing a time resolution of ∝220 ps (FWHM) and a position resolution of ∝270 μm (FWHM) with a detection efficiency ε>99%. The characterization of the spectrometer arm has been achieved through simulations calculating the transfer matrix of track parameters from the fiber detector

  15. SENTIRAD-An innovative personal radiation detector based on a scintillation detector and a silicon photomultiplier

    International Nuclear Information System (INIS)

    The alarming personal radiation detector (PRD) is a device intended for Homeland Security (HLS) applications. This portable device is designed to be worn or carried by security personnel to detect photon-emitting radioactive materials for the purpose of crime prevention. PRD is required to meet the scope of specifications defined by various HLS standards for radiation detection. It is mandatory that the device be sensitive and simultaneously small, pocket-sized, of robust mechanical design and carriable on the user's body. To serve these specialized purposes and requirements, we developed the SENTIRAD, a new radiation detector designed to meet the performance criteria established for counterterrorist applications. SENTIRAD is the first commercially available PRD based on a CsI(Tl) scintillation crystal that is optically coupled with a silicon photomultiplier (SiPM) serving as a light sensor. The rapidly developing technology of SiPM, a multipixel semiconductor photodiode that operates in Geiger mode, has been thoroughly investigated in previous studies. This paper presents the design considerations, constraints and radiological performance relating to the SENTIRAD radiation sensor.

  16. SENTIRAD—An innovative personal radiation detector based on a scintillation detector and a silicon photomultiplier

    Science.gov (United States)

    Osovizky, A.; Ginzburg, D.; Manor, A.; Seif, R.; Ghelman, M.; Cohen-Zada, I.; Ellenbogen, M.; Bronfenmakher, V.; Pushkarsky, V.; Gonen, E.; Mazor, T.; Cohen, Y.

    2011-10-01

    The alarming personal radiation detector (PRD) is a device intended for Homeland Security (HLS) applications. This portable device is designed to be worn or carried by security personnel to detect photon-emitting radioactive materials for the purpose of crime prevention. PRD is required to meet the scope of specifications defined by various HLS standards for radiation detection. It is mandatory that the device be sensitive and simultaneously small, pocket-sized, of robust mechanical design and carriable on the user's body. To serve these specialized purposes and requirements, we developed the SENTIRAD, a new radiation detector designed to meet the performance criteria established for counterterrorist applications. SENTIRAD is the first commercially available PRD based on a CsI(Tl) scintillation crystal that is optically coupled with a silicon photomultiplier (SiPM) serving as a light sensor. The rapidly developing technology of SiPM, a multipixel semiconductor photodiode that operates in Geiger mode, has been thoroughly investigated in previous studies. This paper presents the design considerations, constraints and radiological performance relating to the SENTIRAD radiation sensor.

  17. Extensive Air Shower Detector Array at the Universidad Autonoma de Puebla

    Science.gov (United States)

    Cotzomi, J.; Moreno, E.; Aguilar, S.; Palma, B.; Martinez, O.; Salazar, H.; Villasenor, L.

    2002-07-01

    We describe the operation of an Extensive Air Shower Array located at the campus of the FCFM-BUAP. The array consists of 8 liquid scintillation detectors with a surface of 1 m2 each and a detector spacing of 20 m in a square grid. The array was designed to measure the energy and arrival direction of primary particles that generate extensive air showers (EAS) in the region of 1013 eV - 1016 eV. The angular distribution measured with this array, Cos8(Theta) xSin(Theta), agrees very well with the literature. We also present the measured energies of a number of vertical showers in the range of 5 x1012 eV to 5 x1013 eV.

  18. Study of Scintillator thickness optimization of lens-coupled X-ray imaging detectors

    Science.gov (United States)

    Xie, H.; Du, G.; Deng, B.; Chen, R.; Xiao, T.

    2016-03-01

    Lens-coupled X-ray in-direct imaging detectors are very popular for high-resolution X-ray imaging at the third generation synchrotron radiation facilities. This imaging system consists of a scintilator producing a visible-light image of X-ray beam, a microscope objective, a mirror reflecting at 90° and a CCD camera. When the thickness of the scintillator is matched with the numerical aperture (NA) of the microscope objective, the image quality of experimental results will be improved obviously. This paper used an imaging system at BL13W beamline of Shanghai Synchrotron Radiation Facility (SSRF) to study the matching relation between the scintillator thickness and the NA of the microscope objective with a real sample. By use of the matching relation between the scintillator thickness and the NA of the microscope objective, the optimal imaging results have been obtained.

  19. Spatial response characterization of liquid scintillator detectors using collimated gamma-ray and neutron beams

    International Nuclear Information System (INIS)

    Liquid scintillators are suitable for many applications because they can detect and characterize fast neutrons as well as gamma-rays. This paper presents the response of a 15-cm-in-length×15-cm-in-height×8.2-cm-in-width EJ-309 liquid scintillator with respect to the position of neutron and gamma-ray interactions. Liquid scintillator cells are typically filled with 97% of the scintillating cocktail to address thermal expansion of the liquid in varying temperature conditions. Measurements were taken with collimated 137Cs and 252Cf sources for gamma-ray and neutron mapping of the detector, respectively. MCNPX-PoliMi (ver. 2.0) simulations were also performed to demonstrate the spatial response of the detector. Results show that the detector response is greatest at the center and decreases when the collimated neutron and gamma-ray beam is moved toward the edge of the detector. The measured response in the voxels surrounding the detector center decreased by approximately 6% and 12% for gamma-ray and neutron scans, respectively, when compared to the center voxel. The measured decrease in the detector response was most pronounced at the corners of detector assembly. For the corner voxels located in the bottom row of the detector, the measured response decreased by approximately 39% for both gamma-ray and neutron scans. For the corner voxels located in the top row of the detector, the measured response decreased by approximately 66% and 48% for gamma-ray and neutron scans, respectively. Both measurements and simulations show the inefficient production of secondary charged particles in the voxels located in the top portion of the detector due to the presence of expansion volume. Furthermore, the presence of the expansion volume potentially affects the transport of the scintillation light through the coupling window between the liquid scintillator and the photocathode in the photomultiplier tube. -- Highlights: • EJ-309 response with respect to the particle interaction

  20. A comparison of CsI:Tl and GOS in a scintillator-CCD detector for nuclear medicine imaging

    Science.gov (United States)

    Bugby, S. L.; Jambi, L. K.; Lees, J. E.

    2016-09-01

    A number of portable gamma cameras for medical imaging use scintillator-CCD based detectors. This paper compares the performance of a scintillator-CCD based portable gamma camera with either a columnar CsI:Tl or a pixelated GOS scintillator installed. The CsI:Tl scintillator has a sensitivity of 40% at 140.5 keV compared to 54% with the GOS scintillator. The intrinsic spatial resolution of the pixelated GOS detector was 1.09 mm, over 4 times poorer than for CsI:Tl. Count rate capability was also found to be significantly lower when the GOS scintillator was used. The uniformity was comparable for both scintillators.

  1. Ticor-based scintillation detectors for detection of mixed radiation

    CERN Document Server

    Litvinov, L A; Kolner, V B; Ryzhikov, V D; Volkov, V G; Tarasov, V A; Zelenskaya, O V

    2002-01-01

    Detection of mixed radiation of thermal neutrons and gamma-rays have been realized using a new ceramic material based on small-crystalline long-wave scintillator alpha-Al sub 2 O sub 3 :Ti (Ticor) and lithium fluoride. Characteristics are presented for scintillators with Si-PIN-PD type photoreceivers and PMT under sup 2 sup 3 sup 9 Pu alpha-particles, sup 2 sup 0 sup 7 Bi internal conversion electrons,as well as sup 2 sup 4 sup 1 Am and sup 1 sup 3 sup 7 Cs gamma-quanta. Detection efficiency of thermal neutron is estimated for composite materials based on Ticor and lithium fluoride.

  2. A large area plastic scintillation detector with 4-corner-readout

    CERN Document Server

    Tang, Shu-wen; Zhou, Yong; Sun, Zhi-yu; Zhang, Xue-heng; Wang, Shi-tao; Yue, Ke; Liu, Long-xiang; Fang, Fang; Yan, Duo; Sun, Yu; Wang, Zhao-min

    2015-01-01

    A 760 $\\times$ 760 $\\times$ 30 mm$^3$ plastic scintillation detector viewed by photomultiplier tubes (PMTs) from four corners has been developed, and the detector has been tested with cosmic rays and $\\gamma$ rays. A position-independent effective time T$_{eff}$ has been found, indicating this detector can be used as a TOF detector. The hit position can also be reconstructed by the time from four corners. A TOF resolution of 236 ps and a position resolution of 48 mm have been achieved, and the detection efficiency has also been investigated.

  3. A large area plastic scintillation detector with 4-corner-readout

    Science.gov (United States)

    Tang, Shu-Wen; Yu, Yu-Hong; Zhou, Yong; Sun, Zhi-Yu; Zhang, Xue-Heng; Wang, Shi-Tao; Yue, Ke; Liu, Long-Xiang; Fang, Fang; Yan, Duo; Sun, Yu; Wang, Zhao-Min

    2016-05-01

    A 760 mm × 760 mm × 30 mm plastic scintillation detector viewed by photomultiplier tubes (PMTs) from four corners has been developed, and the detector has been tested with cosmic rays and γ rays. A position-independent effective time T eff has been found, indicating this detector can be used as a TOF detector. The hit position can also be reconstructed by the time from the four corners. A TOF resolution of 236 ps and a position resolution of 48 mm have been achieved, and the detection efficiency has also been investigated. Supported by National Natural Science Foundation of China (U1332207, 11405242)

  4. The research program of the Liquid Scintillation Detector (LSD) in the Mont Blanc Laboratory

    Science.gov (United States)

    Dadykin, V. L.; Yakushev, V. F.; Korchagin, P. V.; Korchagin, V. B.; Malgin, A. S.; Ryassny, F. G.; Ryazhskaya, O. G.; Talochkin, V. P.; Zatsepin, G. T.; Badino, G.

    1985-01-01

    A massive (90 tons) liquid scintillation detector (LSD) has been running since October 1984 in the Mont Blanc Laboratory at a depth of 5,200 hg/sq cm of standard rock. The research program of the experiment covers a variety of topics in particle physics and astrophysics. The performance of the detector, the main fields of research are presented and the preliminary results are discussed.

  5. Development of a mini high efficiency neutron detector based on 6LiI (Eu) scintillator

    International Nuclear Information System (INIS)

    A mini neutron detector with the dimension of φ25 mm ×20 mm is developed based on a 6LiI( Eu) scintillator with a Hamamatsu S3590-08 photodiode. The detector was used to detect thermal neutrons from a paraffin shielded 252Cf neutron source and the detect efficiency to thermal neutron was calculated to be 95% with a resolution of thermal neutron peak about 16%. (authors)

  6. Spiral biasing adaptor for use in Si drift detectors and Si drift detector arrays

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zheng; Chen, Wei

    2016-07-05

    A drift detector array, preferably a silicon drift detector (SDD) array, that uses a low current biasing adaptor is disclosed. The biasing adaptor is customizable for any desired geometry of the drift detector single cell with minimum drift time of carriers. The biasing adaptor has spiral shaped ion-implants that generate the desired voltage profile. The biasing adaptor can be processed on the same wafer as the drift detector array and only one biasing adaptor chip/side is needed for one drift detector array to generate the voltage profiles on the front side and back side of the detector array.

  7. Gamma Ray Array Detector Trigger Sub-System

    CERN Document Server

    Zhong-Wei, Du; Yi, Qian; KongJie,

    2012-01-01

    Gamma Ray Array Detector (GRAD) is one of External Target Facility (ETF) subsystems at the Heavy Ion Research Facility at Lanzhou. The trigger subsystem of the GRAD has been developed based on Field Programmable Gate Array (FPGAs) and PXI interface. The GRAD trigger subsystem makes prompt L1 trigger decisions to select valid events. These decisions are made by processing the hit signals from 1024 CsI scintillators of the GRAD. According to the physical requirements, the GRAD trigger subsystem generates 12-bit trigger signals that are passed to the ETF global trigger system. In addition, the GRAD trigger subsystem generates trigger data that are packed and transmitted to the host computer via PXI bus for off-line analysis. The trigger processing is implemented in the front-end electronics and one FPGA of the trigger module. The logic of PXI transmission and reconfiguration is implemented in the other FPGA of the trigger module. The reliable and efficient performance in the Gamma-ray experiments demonstrates th...

  8. Study of the penetrating component of cosmic rays underground using large scintillation detectors

    Science.gov (United States)

    Ryazhskaya, O. G.

    2016-05-01

    The study of penetrating component of cosmic ray underground using large scintillation detectors situated in Russia and Italy is carried out during more than 40 years. The main results obtained at the different depths from 25 m w.e. to 5200 m w.e. are presented in this report.

  9. Development of a thermal neutron detector based on scintillating fibers and silicon photomultipliers

    International Nuclear Information System (INIS)

    We propose a technique for thermal neutron detection, based on a 6Li converter placed in front of scintillating fibers readout by means of silicon photomultipliers. Such a technique allows building cheap and compact detectors and dosimeters, thus possibly opening new perspectives in terms of granular monitoring of neutron fluxes as well as space-resolved neutron detection.

  10. Monte Carlo based calibration of scintillation detectors for laboratory and in situ gamma ray measurements

    NARCIS (Netherlands)

    van der Graaf, E. R.; Limburg, J.; Koomans, R. L.; Tijs, M.

    2011-01-01

    The calibration of scintillation detectors for gamma radiation in a well characterized setup can be transferred to other geometries using Monte Carlo simulations to account for the differences between the calibration and the other geometry. In this study a calibration facility was used that is const

  11. New scintillators for focal plane detectors in gamma-ray missions

    NARCIS (Netherlands)

    Buis, Ernst-Jan; Beijersbergen, Marco; Kraft, Stefan; Owens, Alan; Quarati, Francesco; Brandenburg, Sytze; Ostendorf, Reint

    2005-01-01

    Recent developments of cerium-doped lanthanum-halide scintillators like LaBr3:Ce show a remarkable performance in gamma-ray spectroscopy. When high energy resolution in combination with stopping power is required they provide excellent gamma-ray detector candidates for the use in space missions. Mor

  12. Dosimetric characterization of the Exradin W1 plastic scintillator detector through comparison with an in-house developed scintillator system

    International Nuclear Information System (INIS)

    New commercial dosimetry systems need careful characterization and can benefit from the comparison with similar, in-house developed solutions. A comparison between such two dosimetry systems, both based on fibre-coupled organic plastic scintillator detectors, is presented. One system is the Exradin W1, fully commercialized by Standard Imaging, while the other system is the non-commercial ME40 system, developed by DTU Nutech with the aim of fundamental dosimetric research. Both systems employ plastic scintillator detectors that can be considered similar in design, calibrated using the same method, but differing primarily in the signal detection hardware. The two systems were compared with respect to essential dosimetric properties, with the purpose of testing their performance under conditions less well discussed in the literature. A Farmer ionization chamber was used as the primary reference of the comparison. The study demonstrated that the Cerenkov light ratio calibration coefficient of both systems was not constant, but changed systematically with photon beam quality to a maximum difference of 1.1%. Calibration with respect to stem effect correction should therefore be performed for every investigated beam quality when using plastic scintillator detectors. Both systems were found to be dose rate independent, even for the highest instantaneous dose rate evaluated (1.5 mGy per pulse). Low-dose measurements revealed large uncertainties for both systems, although the ME40 system handled short beam deliveries under reference conditions with accuracy and precision within 0.4%. Changes in response due to field size dependence were investigated and found to be as large as 3.3% for the W1 and 5.4% for the ME40, biasing output factor measurements in large fields. Great caution is therefore advised if using either system for measurements in large fields or under circumstances where the fibre irradiation geometry is unfavourable. Measurements of reference dose to water

  13. Low-energy CZT detector array for the ASIM mission

    DEFF Research Database (Denmark)

    Cenkeramaddi, Linga Reddy; Genov, Georgi; Kohfeldt, Anja;

    2012-01-01

    In this article we introduce the low-energy CZT (CdZnTe) 16 384-pixel detector array on-board the Atmosphere Space Interaction Monitor (ASIM), funded by the European Space Agency. This detector is a part of the larger Modular X-and Gamma-ray sensor (MXGS). The CZT detector array is sensitive...

  14. A scintillating-glass fiber optic vertex and tracking detector

    International Nuclear Information System (INIS)

    High resolution tracking capability is essential for the study of heavy particle production and decay in high energy interactions and for the pattern recognition of high energy events at colliders. Instead of pursuing conventional solutions to the micro-tracking problem such as Si microstrips, drift chambers, or CCDs, we have been following a more unconventional approach, the development of a scintillating glass, fiber-optic imaging system. The initial goal of this program has been to produce a high resolution active target for fixed-target applications; the longer range goal is to exploit the power of fiber-optic techniques for vertex detection and tracking in colliding beam applications

  15. Design and development of compact readout electronics with silicon photomultiplier array for a compact imaging detector

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-Hui; QI Yu-Jin; ZHAO Cui-Lan

    2012-01-01

    This work aims at developing compact readout electronics for a compact imaging detector module with silicon photomultiplier (SPM) array.The detector module consists of a LYSO crystal array coupling with a SensL's 4×4 SPM array.A compact multiplexed readout based on a discretized positioning circuit (DPC) was developed to reduce the readout channels from 16 to 4 outputs.Different LYSO crystal arrays of 4×4,8×8 and 12×12 with pixel sizes of 3.2,1.6 and 1.0 mm respectively,have been tested with the compact readout board using a 137Cs source.The initial results show that the compact imaging detector module with the compact multiplexed readout could clearly resolve 1 mm×1 mm×10 mm LYSO scintillation crystal array except those at the edges.The detector's intrinsic spatial resolution up to 1 mm can be achieved with the 3 mm×3 mm size SPMArray4 through light sharing and compact multiplexed readout.Our results indicate that this detector module is feasible for the development of high-resolution compact PET.

  16. Evaluating scintillators used in radiation detectors of medical imaging systems by the effective fidelity index method

    International Nuclear Information System (INIS)

    Objective: The performance of medical X-ray image receptors depends: (1) on the scintillator light emission efficiency; and (2) on the compatibility of the scintillator light spectrum with the spectral sensitivity of the light detector (film, photocathode, or photodiode), employed in conjunction with the scintillator. In this study, a scintillator performance measure, the effective fidelity index (EFI), is defined as function of both the scintillator light emission efficiency and spectral compatibility. Materials and Method: CsI:Na, Gd2O2S:Tb and La2O2S:Tb scintillators were employed in the form of phosphor screens prepared in our laboratory with various coating thicknesses. The screens were irradiated with X-rays employing tube voltages ranging between 50-120 kVp. Results: The EFI performance of CsI:Na was found to increase with screen coating thickness and it was best when combined with the orthochromatic film or the ES/20 photocathode. Gd2O2S:Tb showed peak EFI performance at 70 mg/cm2 coating thickness and it was well combined with the light detectors considered. Conclusion: In accordance with our results, CsI:Na may be employed in radiography when adequately protected against humidity. Gd2O2S:Tb suitability for conventional imaging was verified and it was found that it may be useful in all types of digital imaging. La2O2S:Tb could also be used in digital detectors of imaging applications demanding medium X-ray tube voltages

  17. Hybrid metal organic scintillator materials system and particle detector

    Science.gov (United States)

    Bauer, Christina A.; Allendorf, Mark D.; Doty, F. Patrick; Simmons, Blake A.

    2011-07-26

    We describe the preparation and characterization of two zinc hybrid luminescent structures based on the flexible and emissive linker molecule, trans-(4-R,4'-R') stilbene, where R and R' are mono- or poly-coordinating groups, which retain their luminescence within these solid materials. For example, reaction of trans-4,4'-stilbenedicarboxylic acid and zinc nitrate in the solvent dimethylformamide (DMF) yielded a dense 2-D network featuring zinc in both octahedral and tetrahedral coordination environments connected by trans-stilbene links. Similar reaction in diethylformamide (DEF) at higher temperatures resulted in a porous, 3-D framework structure consisting of two interpenetrating cubic lattices, each featuring basic to zinc carboxylate vertices joined by trans-stilbene, analogous to the isoreticular MOF (IRMOF) series. We demonstrate that the optical properties of both embodiments correlate directly with the local ligand environments observed in the crystal structures. We further demonstrate that these materials produce high luminescent response to proton radiation and high radiation tolerance relative to prior scintillators. These features can be used to create sophisticated scintillating detection sensors.

  18. Improvement of an X-ray imaging detector based on a scintillating guides screen

    CERN Document Server

    Badel, X; Linnros, J; Kleimann, P; Froejdh, C; Petersson, C S

    2002-01-01

    An X-ray imaging detector has been developed for dental applications. The principle of this detector is based on application of a silicon charge coupled device covered by a scintillating wave-guide screen. Previous studies of such a detector showed promising results concerning the spatial resolution but low performance in terms of signal to noise ratio (SNR) and sensitivity. Recent results confirm the wave-guiding properties of the matrix and show improvement of the detector in terms of response uniformity, sensitivity and SNR. The present study is focussed on the fabrication of the scintillating screen where the principal idea is to fill a matrix of Si pores with a CsI scintillator. The photoluminescence technique was used to prove the wave-guiding property of the matrix and to inspect the filling uniformity of the pores. The final detector was characterized by X-ray evaluation in terms of spatial resolution, light output and SNR. A sensor with a spatial resolution of 9 LP/mm and a SNR over 50 has been achie...

  19. Improvement of an X-ray imaging detector based on a scintillating guides screen

    International Nuclear Information System (INIS)

    An X-ray imaging detector has been developed for dental applications. The principle of this detector is based on application of a silicon charge coupled device covered by a scintillating wave-guide screen. Previous studies of such a detector showed promising results concerning the spatial resolution but low performance in terms of signal to noise ratio (SNR) and sensitivity. Recent results confirm the wave-guiding properties of the matrix and show improvement of the detector in terms of response uniformity, sensitivity and SNR. The present study is focussed on the fabrication of the scintillating screen where the principal idea is to fill a matrix of Si pores with a CsI scintillator. The photoluminescence technique was used to prove the wave-guiding property of the matrix and to inspect the filling uniformity of the pores. The final detector was characterized by X-ray evaluation in terms of spatial resolution, light output and SNR. A sensor with a spatial resolution of 9 LP/mm and a SNR over 50 has been achieved using a standard dental X-ray source and doses in the order of those used at the moment by dentists (around 25 mR)

  20. Evaluation of Large Volume SrI2(Eu) Scintillator Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Sturm, B W; Cherepy, N J; Drury, O B; Thelin, P A; Fisher, S E; Magyar, A F; Payne, S A; Burger, A; Boatner, L A; Ramey, J O; Shah, K S; Hawrami, R

    2010-11-18

    There is an ever increasing demand for gamma-ray detectors which can achieve good energy resolution, high detection efficiency, and room-temperature operation. We are working to address each of these requirements through the development of large volume SrI{sub 2}(Eu) scintillator detectors. In this work, we have evaluated a variety of SrI{sub 2} crystals with volumes >10 cm{sup 3}. The goal of this research was to examine the causes of energy resolution degradation for larger detectors and to determine what can be done to mitigate these effects. Testing both packaged and unpackaged detectors, we have consistently achieved better resolution with the packaged detectors. Using a collimated gamma-ray source, it was determined that better energy resolution for the packaged detectors is correlated with better light collection uniformity. A number of packaged detectors were fabricated and tested and the best spectroscopic performance was achieved for a 3% Eu doped crystal with an energy resolution of 2.93% FWHM at 662keV. Simulations of SrI{sub 2}(Eu) crystals were also performed to better understand the light transport physics in scintillators and are reported. This study has important implications for the development of SrI{sub 2}(Eu) detectors for national security purposes.

  1. Gamma ray measurement of earth formation properties using a position sensitive scintillation detector

    International Nuclear Information System (INIS)

    This patent describes a system for measuring properties of earth formations in the vicinity of a well borehole at different radial distances from the borehole, comprising: a fluid tight hollow body member sized and adapted for passage through a well borehole and housing therein; a source of gamma rays and means for directing gamma rays from the source outwardly from the body member into earth formations in the vicinity of the borehole; and a position sensitive scintillation detector for detecting gamma rays scattered back into the body member from the earth formation in the vicinity of the borehole, means for collimating the scattered gamma rays onto the detector. The detector comprises scintillation crystal means having discrete longitudinally spaced active regions or bins and is longitudinally spaced from the gamma ray source. It has a longitudinal length L and two opposite ends and photomultiplier tubes optically coupled to the opposite ends for providing output voltage signals having voltage amplitudes A and B representative of the intensity of scintillation events occurring in the crystal and impinging at the opposite ends thereof. A means separates the bins for selectively attenuating light passing therebetween, and a means combines the output voltage signals A and B according to a predetermined relationship to derive the discrete bin along the length L of each of the scintillation events in the crystal, thereby providing measurements of the gamma ray scattering properties of the earth formations at different radial distances from the borehole

  2. Sapphire scintillation tests for cryogenic detectors in the Edelweiss dark matter search

    Energy Technology Data Exchange (ETDEWEB)

    Luca, M

    2007-07-15

    Identifying the matter in the universe is one of the main challenges of modern cosmology and astrophysics. An important part of this matter seems to be made of non-baryonic particles. Edelweiss is a direct dark matter search using cryogenic germanium bolometers in order to look for particles that interact very weakly with the ordinary matter, generically known as WIMPs (weakly interacting massive particles). An important challenge for Edelweiss is the radioactive background and one of the ways to identify it is to use a larger variety of target crystals. Sapphire is a light target which can be complementary to the germanium crystals already in use. Spectroscopic characterization studies have been performed using different sapphire samples in order to find the optimum doping concentration for good low temperature scintillation. Ti doped crystals with weak Ti concentrations have been used for systematic X ray excitation tests both at room temperature and down to 30 K. The tests have shown that the best Ti concentration for optimum room temperature scintillation is 100 ppm and 50 ppm at T = 45 K. All concentrations have been checked by optical absorption and fluorescence. After having shown that sapphire had interesting characteristics for building heat-scintillation detectors, we have tested if using a sapphire detector was feasible within a dark matter search. During the first commissioning tests of Edelweiss-II, we have proved the compatibility between a sapphire heat scintillation detector and the experimental setup. (author)

  3. Application of miniature plastic scintillation detectors to proton therapy beam dosimetry

    International Nuclear Information System (INIS)

    Plastic scintillators have previously been used extensively in high energy nuclear spectroscopy experiments. Such scintillators were fairly large sized and were mainly applied for beam time structure, energy of events and time of flight measurements. Recently, miniature plastic scintillation detectors have been successfully applied to high energy photon and electron radiotherapy dosimetry and field mapping. Some of the principal advantages of using these detectors is that the usual conversion of dose from one medium to another can be avoided, the perturbation of the radiation field is minimal and small size permits accurate dose measurements in regions of high dose gradients. The technical advantages of scintillation dosimetry make them appealing to proton radiotherapy where high dose gradients produced by the Bragg peak are used. In this regard, we have investigated their use in the measurement of dose in clinical proton beams. Field mapping measurements in proton beams with different initial energies will be presented and compared to those obtained using a standard parallel plate ionization chamber. Among other dosimetric characteristics of these detectors, the radiation induced effects on optical fibers in such an environment will be presented and discussed

  4. A compact gamma-ray detector using wavelength-shifting fibers coupled to YAP scintillation crystal

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The performance of a compact position sensitive gamma-ray detector based on wavelength-shifting fibers coupled to YAlO3:Ce scintillation crystal was evaluated using a Monte-Carlo simulation method.The simulation model has been setup using the GEANT4 codes.Compared with the gamma-ray detector based on the YAlO3:Ce scintillation crystal coupled to Hamamastu R2486 position sensitive photomultiplier tube.the results indicate that the gamma-ray detector based on wavelength-shifting fibers readout has good position linearity,good spatial resolution and larger effective field of view.The image and point spread function of measured point were presented.The spatial resolution reaponse as a function of position was obtained.The factors influencing spatial resolution and position linearity were discussed.

  5. Master plan for the development of ZnS scintillation neutron detectors for NDA

    International Nuclear Information System (INIS)

    Alternative techniques to neutron detection by He-3 for safeguards and nuclear security systems are necessary to be developed since He-3 gas shortage is serious. With support of Japanese government (MEXT), we have started an R and D project of ZnS ceramic scintillation neutron detectors for non-destructive assay (NDA) of Pu in Fresh MOX fuel and other types of nuclear material for a use of safeguards verification. Here we present master plan of the R and D project and feasibility study on neutron absorption probability in our scintillator by using Monte Carlo code. (author)

  6. Improved Growth Methods for LaBr3 Scintillation Radiation Detectors

    Energy Technology Data Exchange (ETDEWEB)

    McGregor, Douglas S

    2011-05-01

    The objective is to develop advanced materials for deployment as high-resolution gamma ray detectors. Both LaBr3 and CeBr3 are advanced scintillation materials, and will be studied in this research. Prototype devices, in collaboration Sandia National Laboratories, will be demonstrated along with recommendations for mass production and deployment. It is anticipated that improved methods of crystal growth will yield larger single crystals of LaBr3 for deployable room-temperature operated gamma radiation spectrometers. The growth methods will be characterized. The LaBr3 and CeBr3 scintillation crystals will be characterized for light yield, spectral resolution, and for hardness.

  7. A CsI(Tl) Scintillating Crystal Detector for the Studies of Low Energy Neutrino Interactions

    CERN Document Server

    Li, H B; Chang, C C; Chang, C Y; Chao, J H; Chen Chi Ping; Chen, T Y; He, M; Hou, L; Kiang, G C; Lai, W P; Lee, S C; Li, J; Lu, J G; Mao, Z P; Sheng, H Y; Su, R F; Teng, P K; Wang, C W; Wang Shui Cai; Wong, H T; Yeh, T R; Zhang, Z Y; Zhao, D X; Zhao, S Q; Zhou, Z Y; Zhuang, B A

    2001-01-01

    Scintillating crystal detector may offer some potential advantages in the low-energy, low-background experiments. A 500~kg CsI(Tl) detector to be placed near the core of Nuclear Power Station II in Taiwan is being constructed for the studies of electron-neutrino scatterings and other keV$-$MeV range neutrino interactions. The motivations of this detector approach, the physics to be addressed, the basic experimental design, and the characteristic performance of prototype modules are described. The expected background channels and their experimental handles are discussed.

  8. A CsI(Tl) Scintillating Crystal Detector for the Studies of Low Energy Neutrino Interactions

    OpenAIRE

    TEXONO Collaboration

    1999-01-01

    Scintillating crystal detector may offer some potential advantages in the low-energy, low-background experiments. A 500 kg CsI(Tl) detector to be placed near the core of Nuclear Power Station II in Taiwan is being constructed for the studies of electron-neutrino scatterings and other keV-MeV range neutrino interactions. The motivations of this detector approach, the physics to be addressed, the basic experimental design, and the characteristic performance of prototype modules are described. T...

  9. An algorithm for automatic crystal identification in pixelated scintillation detectors using thin plate splines and Gaussian mixture models

    Science.gov (United States)

    Schellenberg, Graham; Stortz, Greg; Goertzen, Andrew L.

    2016-02-01

    A typical positron emission tomography detector is comprised of a scintillator crystal array coupled to a photodetector array or other position sensitive detector. Such detectors using light sharing to read out crystal elements require the creation of a crystal lookup table (CLUT) that maps the detector response to the crystal of interaction based on the x-y position of the event calculated through Anger-type logic. It is vital for system performance that these CLUTs be accurate so that the location of events can be accurately identified and so that crystal-specific corrections, such as energy windowing or time alignment, can be applied. While using manual segmentation of the flood image to create the CLUT is a simple and reliable approach, it is both tedious and time consuming for systems with large numbers of crystal elements. In this work we describe the development of an automated algorithm for CLUT generation that uses a Gaussian mixture model paired with thin plate splines (TPS) to iteratively fit a crystal layout template that includes the crystal numbering pattern. Starting from a region of stability, Gaussians are individually fit to data corresponding to crystal locations while simultaneously updating a TPS for predicting future Gaussian locations at the edge of a region of interest that grows as individual Gaussians converge to crystal locations. The algorithm was tested with flood image data collected from 16 detector modules, each consisting of a 409 crystal dual-layer offset LYSO crystal array readout by a 32 pixel SiPM array. For these detector flood images, depending on user defined input parameters, the algorithm runtime ranged between 17.5-82.5 s per detector on a single core of an Intel i7 processor. The method maintained an accuracy above 99.8% across all tests, with the majority of errors being localized to error prone corner regions. This method can be easily extended for use with other detector types through adjustment of the initial

  10. An algorithm for automatic crystal identification in pixelated scintillation detectors using thin plate splines and Gaussian mixture models.

    Science.gov (United States)

    Schellenberg, Graham; Stortz, Greg; Goertzen, Andrew L

    2016-02-01

    A typical positron emission tomography detector is comprised of a scintillator crystal array coupled to a photodetector array or other position sensitive detector. Such detectors using light sharing to read out crystal elements require the creation of a crystal lookup table (CLUT) that maps the detector response to the crystal of interaction based on the x-y position of the event calculated through Anger-type logic. It is vital for system performance that these CLUTs be accurate so that the location of events can be accurately identified and so that crystal-specific corrections, such as energy windowing or time alignment, can be applied. While using manual segmentation of the flood image to create the CLUT is a simple and reliable approach, it is both tedious and time consuming for systems with large numbers of crystal elements. In this work we describe the development of an automated algorithm for CLUT generation that uses a Gaussian mixture model paired with thin plate splines (TPS) to iteratively fit a crystal layout template that includes the crystal numbering pattern. Starting from a region of stability, Gaussians are individually fit to data corresponding to crystal locations while simultaneously updating a TPS for predicting future Gaussian locations at the edge of a region of interest that grows as individual Gaussians converge to crystal locations. The algorithm was tested with flood image data collected from 16 detector modules, each consisting of a 409 crystal dual-layer offset LYSO crystal array readout by a 32 pixel SiPM array. For these detector flood images, depending on user defined input parameters, the algorithm runtime ranged between 17.5-82.5 s per detector on a single core of an Intel i7 processor. The method maintained an accuracy above 99.8% across all tests, with the majority of errors being localized to error prone corner regions. This method can be easily extended for use with other detector types through adjustment of the initial

  11. Fast Neutron Detector for Fusion Reactor KSTAR Using Stilbene Scintillator

    CERN Document Server

    Lee, Seung Kyu; Kim, Gi-Dong; Kim, Yong-Kyun

    2011-01-01

    Various neutron diagnostic tools are used in fusion reactors to evaluate different aspects of plasma performance, such as fusion power, power density, ion temperature, fast ion energy, and their spatial distributions. The stilbene scintillator has been proposed for use as a neutron diagnostic system to measure the characteristics of neutrons from the Korea Superconducting Tokamak Advanced Research (KSTAR) fusion reactor. Specially designed electronics are necessary to measure fast neutron spectra with high radiation from a gamma-ray background. The signals from neutrons and gamma-rays are discriminated by the digital charge pulse shape discrimination (PSD) method, which uses total to partial charge ratio analysis. The signals are digitized by a flash analog-to-digital convertor (FADC). To evaluate the performance of the fabricated stilbene neutron diagnostic system, the efficiency of 10 mm soft-iron magnetic shielding and the detection efficiency of fast neutrons were tested experimentally using a 252Cf neutr...

  12. The PRESHOWER - a New Multichnnel Detector for the CDF. The Scintillator Plates of the New Detector: Design, Production, Quality Control

    CERN Document Server

    Artikov, A M; Chocheli, D; Danilov, V; Grinyov, B; Lebedev, V; Senchyshyn, V G

    2005-01-01

    To increase the CDF efficiency when studying heavy quark processes there was designed, constructed and put into operation a new multichannel detector --- the so called Central Preshower. It was positioned before the central electromagnetic calorimeter and increased the photon, lepton and hadron identification efficiency. JINR in cooperation with the Institute of Scintillating Materials (Kharkiv) has created a sensitive element of the new detector: about 2800 units of the scintillation tiles; the specially developed quality control procedure guaranteed the necessary high light yield for tiles mass production. The chosen tiles were equipped at FNAL by two loops (about 1 m long) of WLS fibers positioned inside the $\\Omega $-shape groove; it guaranteed a light yield of $\\sim$ 25--35 photoelectrons/MIP.

  13. Discrimination of cosmic-rays in scintillation region and light-guide for plastic scintillation detectors using 5GSPS readout system

    International Nuclear Information System (INIS)

    At sea level, the measurement of energy spectrum for cosmic-rays flux determination using two-coincidence plastic scintillation detectors with “traditional” electronic-readout system may include not only cosmic-rays in scintillator region but also light-guide region. In this work, we carry out a measurement of cosmic-rays using two-coincidence plastic scintillation detectors with size of each 80 cm × 40 cm × 3 cm thick, and an electronic-readout system of 5GSPS (i.e. 200 psec sampling-time resolution). With the readout system, the shape of pulses from scintillation detectors can be observed. The behavior of time response in plastic scintillator and light-guide may be different. Based on the time response of pulses such as width of pulse, it is possible to discriminate cosmic rays in scintillation region from light-guide region. The obtained results will be presented and discussed in detail. The experiment is set up and measured at the Nuclear laboratory, Department of Nuclear Physics, University of Science, HCMC-Vietnam National University. (author)

  14. The design and the construction of the scintillating fiber detector for the UA2 experiment

    International Nuclear Information System (INIS)

    The scintillating fiber detector (S.F.D.) is a key part of the upgraded UA2 experiment. It includes 60,000 scintillating fibers 1 mm in diameter and 2 m long, arranged in 24 coaxial layers fitting in a cylindrical space from 760 to 880 mm in diameter around the pp-bar intersection. The fiber layers are arranged in 8 stereo triplets. Each one contains one fiber set parallel to the axis, and 2 others inclined at angle +-200 on the average. The S.F.D. has 2 separate functions. The inside layers give a precise localization of the particles, the outside layers also initiate the electromagnetic showers by conversion in a lead sheet 1.5 radiation length thick. Each fiber is optically tested. When not rejected, its scintillating efficiency and attenuation length are recorded. The position of every fiber in space is measured and recorded. Each fiber is individually read out

  15. Gas flow scintillation detector for weak beta emitters and its application to recoil tritium chemistry

    International Nuclear Information System (INIS)

    The scintillation flow counter was employed in a radio gas chromatograph. The scintillation detector utilized anthracene crystals as a fluor. The scintillation flow counter did not quench with the chloroethylene system, gave better peak resolution, exhibited less tailing of the peaks, and returned to the initial background level much faster. A computer program was developed to find and determine the areas of the peaks from the radio gas chromatograph. An improved gas chromatographic separation of the products for the dichloroethylene system was developed utilizing two columns in series and temperature programming. The reaction of recoil tritium with unsaturated carbons of the cis- and trans-1,2-dichloroethylene was studied. The data support the fast, direct substitution mechanism with retention of configuration in the liquid phase. The small geometric isomerization of 1,2-dichloroethylene probably arises from rotation about the ethylenic double bond of the excited 1,2-dichloroethylene molecule produced from the tritium for hydrogen substitution reaction

  16. Spent Nuclear Fuel Cask and Storage Monitoring with 4He Scintillation Fast Neutron Detectors

    International Nuclear Information System (INIS)

    With this increasing quantity of spent nuclear fuel being stored at nuclear plants across S. Korea, the demand exists for building a long-term disposal facility. However, the Korean government first requires a detailed plan for the monitoring and certification of spent fuel. Several techniques have been developed and applied for the purpose of spent fuel monitoring, including the digital Cerenkov viewing device (DCVD), spent fuel attribute tester (SFAT), and FORK detector. Conventional gamma measurement methods, however, suffer from a lack of nuclear data and interfering background radiation. To date, the primary method of neutron detection for spent fuel monitoring has been through the use of thermal neutron detectors such as 3He and BF3 proportional counters. Unfolding the neutron spectrum becomes extremely complicated. In an attempt to overcome these difficulties, a new fast neutron measurement system is currently being developed at the University of Florida. This system is based on the 4He scintillation detector invented by Arktis Radiation Detectors Ltd. These detectors are a relatively new technological development and take advantage of the high 4He cross-section for elastic scattering at fast neutron energies, particularly the resonance around 1 MeV. This novel 4He scintillation neutron detector is characterized by its low electron density, leading to excellent gamma rejection. This detector also has a fast response time on the order of nanoseconds and most importantly, preserves some neutron energy information since no moderator is required. Additionally, these detectors rely on naturally abundant 4He as the fill gas. This study proposes a new technique using the neutron spectroscopy features of 4He scintillation detectors to maintain accountability of spent fuel in storage. This research will support spent fuel safeguards and the detection of fissile material, in order to minimize the risk of nuclear proliferation and terrorism. This study conducted a

  17. Methods to extract more light from minute scintillation crystals used in an ultra-high resolution positron emission tomography detector

    Energy Technology Data Exchange (ETDEWEB)

    Levin, Craig S. E-mail: clevin@stanford.edu; Habte, Frezghi; Foudray, Angela M

    2004-07-11

    Recently, there has been great interest in developing finely pixellated position-sensitive scintillation detectors for ultra-high-resolution Positron Emission Tomography (PET) systems designed for breast cancer detection, diagnosis, and staging and for imaging small laboratory animals. We are developing a different high-resolution PET detector design that promotes nearly complete scintillation light collection in {<=}1 mm wide, >10 mm thick lutetium oxyorthosilicate (LSO) crystals. The design requires the use of semiconductor photodetector arrays in novel configurations that significantly improve the light collection aspect ratio for minute crystals. To reduce design complexity and dead area we are investigating the use of 1 mm thick sheets of LSO in addition to discrete crystal rods, and the use of position-sensitive avalanche photodiodes (PSAPDs) which require only four readout channels per device, in addition to pixellated APD arrays. Using a 1 mm thick scintillation crystal sheet coupled to a finely pixellated APD array results in a pseudo-discrete response to flood irradiation: due to a very narrow light spread function in the thin sheet we observe sharp (<1 mm wide) peaks in sensitivity centered at the APD pixel locations in a very linear fashion all the way out to the crystal edge. We measured an energy resolution of 13.7% FWHM at 511 keV for a 1 mm LSO crystal coupled to two APD pixels. Using a 1 mm thick crystal sheet coupled to a PSAPD the response to flood and edge-on irradiation with a {sup 22}Na point source shows a compressed dynamic range compared to that observed with discrete crystals or direct X-ray irradiation. With a discrete LSO crystal array the flood response is peaked at the crystal location where light is focused onto one spot on the PSAPD. We observed strong pin-cushioning effects in all PSAPD measurements. All LSO-PSAPD configurations studied had high aspect ratio for light collection and achieved energy resolutions {<=}12% FWHM at 511 keV.

  18. Methods to extract more light from minute scintillation crystals used in an ultra-high resolution positron emission tomography detector

    Science.gov (United States)

    Levin, Craig S.; Habte, Frezghi; Foudray, Angela M.

    2004-07-01

    Recently, there has been great interest in developing finely pixellated position-sensitive scintillation detectors for ultra-high-resolution Positron Emission Tomography (PET) systems designed for breast cancer detection, diagnosis, and staging and for imaging small laboratory animals. We are developing a different high-resolution PET detector design that promotes nearly complete scintillation light collection in ⩽1 mm wide, >10 mm thick lutetium oxyorthosilicate (LSO) crystals. The design requires the use of semiconductor photodetector arrays in novel configurations that significantly improve the light collection aspect ratio for minute crystals. To reduce design complexity and dead area we are investigating the use of 1 mm thick sheets of LSO in addition to discrete crystal rods, and the use of position-sensitive avalanche photodiodes (PSAPDs) which require only four readout channels per device, in addition to pixellated APD arrays. Using a 1 mm thick scintillation crystal sheet coupled to a finely pixellated APD array results in a pseudo-discrete response to flood irradiation: due to a very narrow light spread function in the thin sheet we observe sharp (<1 mm wide) peaks in sensitivity centered at the APD pixel locations in a very linear fashion all the way out to the crystal edge. We measured an energy resolution of 13.7% FWHM at 511 keV for a 1 mm LSO crystal coupled to two APD pixels. Using a 1 mm thick crystal sheet coupled to a PSAPD the response to flood and edge-on irradiation with a 22Na point source shows a compressed dynamic range compared to that observed with discrete crystals or direct X-ray irradiation. With a discrete LSO crystal array the flood response is peaked at the crystal location where light is focused onto one spot on the PSAPD. We observed strong pin-cushioning effects in all PSAPD measurements. All LSO-PSAPD configurations studied had high aspect ratio for light collection and achieved energy resolutions ⩽12% FWHM at 511 keV.

  19. Advanced ACTPol Cryogenic Detector Arrays and Readout

    Science.gov (United States)

    Henderson, S. W.; Allison, R.; Austermann, J.; Baildon, T.; Battaglia, N.; Beall, J. A.; Becker, D.; De Bernardis, F.; Bond, J. R.; Calabrese, E.; Choi, S. K.; Coughlin, K. P.; Crowley, K. T.; Datta, R.; Devlin, M. J.; Duff, S. M.; Dunkley, J.; Dünner, R.; van Engelen, A.; Gallardo, P. A.; Grace, E.; Hasselfield, M.; Hills, F.; Hilton, G. C.; Hincks, A. D.; Hloẑek, R.; Ho, S. P.; Hubmayr, J.; Huffenberger, K.; Hughes, J. P.; Irwin, K. D.; Koopman, B. J.; Kosowsky, A. B.; Li, D.; McMahon, J.; Munson, C.; Nati, F.; Newburgh, L.; Niemack, M. D.; Niraula, P.; Page, L. A.; Pappas, C. G.; Salatino, M.; Schillaci, A.; Schmitt, B. L.; Sehgal, N.; Sherwin, B. D.; Sievers, J. L.; Simon, S. M.; Spergel, D. N.; Staggs, S. T.; Stevens, J. R.; Thornton, R.; Van Lanen, J.; Vavagiakis, E. M.; Ward, J. T.; Wollack, E. J.

    2016-08-01

    Advanced ACTPol is a polarization-sensitive upgrade for the 6 m aperture Atacama Cosmology Telescope, adding new frequencies and increasing sensitivity over the previous ACTPol receiver. In 2016, Advanced ACTPol will begin to map approximately half the sky in five frequency bands (28-230 GHz). Its maps of primary and secondary cosmic microwave background anisotropies—imaged in intensity and polarization at few arcminute-scale resolution—will enable precision cosmological constraints and also a wide array of cross-correlation science that probes the expansion history of the universe and the growth of structure via gravitational collapse. To accomplish these scientific goals, the Advanced ACTPol receiver will be a significant upgrade to the ACTPol receiver, including four new multichroic arrays of cryogenic, feedhorn-coupled AlMn transition edge sensor polarimeters (fabricated on 150 mm diameter wafers); a system of continuously rotating meta-material silicon half-wave plates; and a new multiplexing readout architecture which uses superconducting quantum interference devices and time division to achieve a 64-row multiplexing factor. Here we present the status and scientific goals of the Advanced ACTPol instrument, emphasizing the design and implementation of the Advanced ACTPol cryogenic detector arrays.

  20. In-situ calibration of a PMT inside a scintillation detector by means of primary scintillation detection

    CERN Document Server

    Álvarez, V; Cárcel, S; Castel, J; Cebrián, S; Cervera, A; Conde, C A N; Dafni, T; Dias, T H V T; Díaz, J; Egorov, M; Esteve, R; Evtoukhovitch, P; Fernandes, L M P; Ferrario, P; Ferreira, A L; Freitas, E D C; Gehman, V M; Gil, A; Goldschmidt, A; Gómez, H; Gómez-Cadenas, J J; González-Díaz, D; Gutiérrez, R M; Hauptman, J; Morata, J A Hernando; Herrera, D C; Iguaz, F J; Irastorza, I G; Jinete, M A; Labarga, L; Laing, A; Liubarsky, I; Lopes, J A M; Lorca, D; Losada, M; Luzón, G; Marí, A; Martín-Albo, J; Martínez, A; Miller, T; Moiseenko, A; Monrabal, F; Monteiro, C M B; Mora, F J; Moutinho, L M; Vidal, J Muñoz; da Luz, H Natal; Navarro, G; Nebot, M; Nygren, D; Oliveira, C A B; Palma, R; Pérez, J; Aparicio, J L Pérez; Renner, J; Ripoll, L; Rodríguez, A; Rodríguez, J; Santos, F P; Santos, J M F dos; Segui, L; Serra, L; Shuman, D; Simón, A; Sofka, C; Sorel, M; Toledo, J F; Tomás, A; Torrent, J; Tsamalaidze, Z; Vázquez, D; Veloso, J F C A; Villar, J A; Webb, R C; White, J T; Yahlali, N

    2012-01-01

    We have investigated the possibility of calibrating the PMTs of scintillation detectors, using the primary scintillation produced by X-rays to induce single photoelectron response of the PMT. The high-energy tail of this response, can be approximated to an exponential function, under some conditions. In these cases, it is possible to determine the average gain for each PMT biasing voltage from the inverse of the exponent of the exponential fit to the tail, which can be done even if the background and/or noise cover-up most of the distribution. We have compared our results with those obtained by the commonly used single electron response (SER) method, which uses a LED to induce a single photoelectron response of the PMT and determines the peak position of such response, relative to the pedestal peak (the electronic noise peak, which corresponds to 0 photoelectrons). The results of the exponential fit method agree with those obtained by the SER method when the average number of photoelectrons reaching the first...

  1. Development and construction of a detector array for ({gamma},n) experiments at NEPTUN

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Vanessa; Loeher, Bastian; Pietralla, Norbert; Schnorrenberger, Linda; Savran, Deniz; Sonnabend, Kerstin [Institut fuer Kernphysik, Technische Universitaet, Darmstadt (Germany)

    2009-07-01

    The low-energy photon tagger NEPTUN has been built at the superconducting electron accelerator S-DALINAC at TU Darmstadt. This spectrometer generates a tagged photon beam in an energy range between 6 MeV< E{sub {gamma}}<20 MeV. For ({gamma},n) experiments a neutron detector array will be designed in a 4{pi}-geometry consisting of 17 detectors. Each detector contains liquid scintillators so that pulse shape discrimination methods can be applied. Four of the detectors are in addition loaded with 5% {sup 10}B to further discriminate between neutrons and photons via the capture reaction {sup 10}B(n,{alpha}){sup 7}Li. The special conditions, as well as initial developments and construction work is shown. Furthermore, first experiments and efficiency measurements are presented.

  2. Development of phonon and photon detectors for rare events searches using scintillating crystals

    Energy Technology Data Exchange (ETDEWEB)

    Gastaldo, Loredana; Hassel, Clemens; Hendricks, Sebastian; Kempf, Sebastian; Fleischmann, Andreas; Enss, Christian [Kirchhoff Institute for Physics, Heidelberg University, Heidelberg (Germany); Rodrigues, Matias; Loidl, Martin; Gray, David; Navick, Xavier-Francois [Commissariat a l' energie atomique, Saclay (France); Kim, Yong-Hamb [Korean Research Institute of Standards and Science, Daejeon (Korea, Republic of)

    2015-07-01

    The use of scintillating crystals in cryogenic experiments searching for neutrinoless double beta decay and for direct interaction of dark matter particles allows for an efficient background reduction thanks to particle discrimination. We develop phonon and photon detectors based on metallic magnetic calorimeters (MMCs)to perform the simultaneous measurement of heat and light generated upon the interaction of a particle in a scintillating crystal. The design values for the energy resolution and signal rise-time are: ΔE{sub FWHM}<100 eV and τ< 200 μs for the phonon detector while for the photon detector we expect ΔE{sub FWHM}<5 eV and τ<50 μs. Proof-of-principle experiments have been already performed within the AMoRE and LUMINEU projects by coupling first prototypes of MMC-based photon and phonon sensors to {sup 100}Mo-based scintillating crystals, CaMoO{sub 4} and ZnMoO{sub 4}. We discuss the design and the fabrication of these detectors and present recent results.

  3. Iterative Monte Carlo simulation with the Compton kinematics-based GEB in a plastic scintillation detector

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chankyu; Kim, Yewon [Department of Nuclear and Quantum Engineering, KAIST, Daejeon 305-701 (Korea, Republic of); Moon, Myungkook [Neutron Instrumentation Division, KAERI, Daejeon 305-353 (Korea, Republic of); Cho, Gyuseong, E-mail: gscho@kaist.ac.kr [Department of Nuclear and Quantum Engineering, KAIST, Daejeon 305-701 (Korea, Republic of)

    2015-09-21

    Plastic scintillators have been used for gamma ray detection in the fields of dosimetry and homeland security because of their desired characteristics such as a fast decay time, a low production cost, availability in a large-scale, and a tissue-equivalence. Gaussian energy broadening (GEB) in MCNP simulation is an effective treatment for tallies to calculate the broadened response function of a detector similarly to measured spectra. The full width at half maximum (FWHM) of a photopeak has been generally used to compute input parameters required for the GEB treatment. However, it is hard to find the photopeak in measured gamma spectra with plastic scintillators so that computation of the input parameters for the GEB has to be taken with another way. In this study, an iterative method for the GEB treated MCNP simulation to calculate the response function of a plastic scintillator is suggested. Instead of the photopeak, Compton maximum and Compton edge were used to estimate energy broadening in the measured spectra and to determine the GEB parameters. In a demonstration with a CsI(Tl) scintillator, the proposed iterative simulation showed the similar gamma spectra to the existing method using photopeaks. The proposed method was then applied to a polystyrene scintillator, and the simulation result were in agreement with the measured spectra with only a little iteration.

  4. Testing and characterization of a fast scintillator detector

    International Nuclear Information System (INIS)

    In this paper, we report, in part, the designing and fabrication of a multi-detector system suitable for investigating the lifetime of a nucleonic state using a particle-gamma correlation setup at the University of Delhi's Nuclear Physics laboratory. Our aim is to identify the beta decay of the mother nucleus to tag that daughter nucleus, which we are interested to study for lifetime measurements. Then fast timing detectors would be used to measure the lifetime of the tagged nucleonic state. Generally we are interested to study nuclei with lifetime in the nanosecond ranges. For gamma-decay measurements, fast timing detectors such as BaF2, LaBr3(Ce) are used, accompanied by electronic timing methods. At our lab, we have recently procured CeBr3 crystals and are in the process of designing a composite particle-gamma correlation detector setup. Our laboratory has the facility to populate desired nucleonic states by neutron activation technique

  5. Characterization of liquid scintillation detector (BC-501A) and digital pulse shape discrimination (DPSD) system

    Energy Technology Data Exchange (ETDEWEB)

    Lombigit, L., E-mail: lojius@nm.gov.my; Yussup, N., E-mail: nolida@nm.gov.my; Ibrahim, Maslina Mohd; Rahman, Nur Aira Abd; Rawi, M. Z. M. [Instrumentation Group, Malaysian Nuclear Agency, Bangi, 43000 Kajang, Selangor (Malaysia)

    2015-04-29

    A digital n/γ pulse shape discrimination (PSD) system is currently under development at Instrumentation and Automation Centre, Malaysian Nuclear Agency. This system aims at simultaneous detection of fast neutron and gamma ray in mixed radiations environment. This work reports the system characterization performed on the liquid scintillation detector (BC-501A) and digital pulse shape discrimination (DPSD) system. The characterization involves measurement of electron light output from the BC-501A detector and energy channels calibration of the pulse height spectra acquired with DPSD system using set of photon reference sources. The main goal of this experiment is to calibrate the ADC channel of our DPSD system, characterized the BC-501 detector and find the position of Compton edge which later could be used as threshold for the n/γ PSD experiment. The detector resolution however is worse as compared to other published data but it is expected as our detector has a smaller active volume.

  6. A large-scale low-background liquid scintillation detector: the counting test facility at Gran Sasso

    International Nuclear Information System (INIS)

    A 4.8 m3 unsegmented liquid scintillation detector at the underground Laboratori Nazionali del Gran Sasso has shown the feasibility of multi-ton low-background detectors operating to energies as low as 250 keV. Detector construction and the handling of large volumes of liquid scintillator to minimize the background are described. The scintillator, 1.5 g PPO/L-pseudocumene, is held in a flexible nylon vessel shielded by 1000 t of purified water. The active detector volume is viewed by 100 photomultipliers, which measure time and charge for each event, from which energy, position and pulse shape are deduced. On-line purification of the scintillator by water extraction, vacuum distillation and nitrogen stripping removed radioactive impurities. Upper limits were established of -7 Bq/kg-scintillator for events with energies 250 keV-9 Bq/kg-scintillator due to the decay products of uranium and thorium. The isotopic abundance of 14C/12C in the scintillator was shown to be approximately 10-18 by extending the energy window of the detector to 25-250 keV. The 14C abundance and uranium and thorium levels in the CTF are compatible with the Borexino Solar Neutrino Experiment. (orig.)

  7. Pulse shape discrimination in helium-4 scintillation detectors

    Science.gov (United States)

    Kelley, Ryan P.; Enqvist, Andreas; Jordan, Kelly A.

    2016-09-01

    Three algorithms were investigated for discriminating between neutrons and gamma rays in a pressurized 4He gas fast neutron detector: charge comparison, weighted integration, and neutron-gamma model analysis (NGMA). For each algorithm, a comprehensive pulse shape discrimination study was conducted using time-of-flight measurements, receiver operator characteristic curves, figure of merit performance measures, and a comparison of performance between 252Cf and PuBe mixed neutron/gamma sources. The NGMA method was found to have the best overall performance by both the figure of merit and the receiver operator characteristic curve. The results also illustrated the high gamma rejection efficiency of these detectors, which is desirable in a variety of neutron monitoring applications.

  8. Detection efficiency simulation and measurement of 6LiI/natLiI scintillation detector

    International Nuclear Information System (INIS)

    Background: Being of very high detection efficiency and small size, Lithium iodide (LiI) scintillator detector is used extensively in neutron measurement and environmental monitoring. Purpose: Using thermal reactor, neutron detectors will be tested and calibrated. And a new neutron detector device will be designed and studied. Methods: The relationship between the size and detection efficiency of the thermal neutron detector 6LiI/natLil was studied using Monte Carlo code GEANT4 and MCNP5 package, and the thermal neutron efficiency of detector was calibrated by reactor neutrons. Results: The theoretical simulation shows that the thermal neutron detection efficiency of detector of 10-mm thickness is relatively high, the enriched 6Lil is up to 98% and the nature natLiI 65%. The thermal neutron efficiency of detector is calibrated by reactor thermal neutrons. Considering the neutron scattering by the lead brick, high density polythene and environment neutron contribution, the detection efficiency of 6LiI detector is about 90% and natLiI detector 70%. Conclusion: The detector efficiency can reach the efficiency value of theoretical calculations. (authors)

  9. Response matrices of NE213 scintillation detectors for neutrons

    International Nuclear Information System (INIS)

    Four NE213 detectors of different size have been calibrated at the accelerator facility of the PTB. The response functions were experimentally determined for 33 neutron energies between 1 MeV and 16 MeV and compared with Monte Carlo simulations using the NRESP7 code. The light output functions for recoil protons were found to be significantly different for all detectors even if they were of the same size. The neutron fluence determined on the basis of the response functions calculated with the corresponding light output functions agreed to better than ±2% with reference values if energy independent adjustment factors between 0.98 and 1.03 were applied. The response matrices required for the unfolding of neutron induced pulse height spectra were therefore calculated with the NRESP7 code taking into account the adjustment factors. Similarly, the response matrices for photons were calculated with the EGS4 code, but without any adjustment. Finally, the DIFBAS code was applied for the unfolding of pure neutron- and photon-induced pulse height spectra. The resulting spectral fluences are in reasonable agreement with the results obtained by time-of-flight measurements and by spectrometry with a Ge detector

  10. Modeling Scintillator-photodiodes As Detectors For Megavoltage Computed Tomography

    CERN Document Server

    Monajemi, T T

    2004-01-01

    The imaging characteristics of a cadmium tungstate, CdWO 4, detector was modeled and measured in 1.25 MeV and 6 MV beams. The detector includes eight CdWO4 crystals, each 2.75 x 8 x 10 mm 3, bonded together and in contact with sixteen silicon photodiodes such that, each crystal covers two photodiodes. The characteristics investigated are the frequency dependent modulation transfer function, MTF (f), noise power spectrum, NPS (f), and detective quantum efficiency, DQE (f). The tools used in modeling these characteristics include the Monte Carlo simulation codes, EGSnrc and DETECT2000, for high energy and optical photons, respectively. The DQE of the detector was found to be approximately constant at 26% and 19% for 1.25 MeV and 6 MV photons up to a spatial frequency of 0.16 cycles/mm, respectively. Due to pulse to pulse fluctuations in the output of the linear accelerator, the NPS(f) and DQE(f) were not verified experimentally in a 6 MV beam.

  11. A First Comparison of the responses of a He4-based fast-neutron detector and a NE-213 liquid-scintillator reference detector

    CERN Document Server

    Jebali, R; Annand, J R M; Chandra, R; Davatz, G; Fissum, K G; Friederich, H; Gendotti, U; Hall-Wilton, R; Håkansson, E; Kanaki, K; Lundin, M; Murer, D; Nilsson, B; Rosborg, A; Svensson, H

    2015-01-01

    A first comparison has been made between the pulse-shape discrimination characteristics of a novel He4-based pressurized scintillation detector and a NE-213 liquid-scintillator reference detector using an Am/Be mixed-field neutron and gamma-ray source and a high-resolution scintillation-pulse digitizer. In particular, the capabilities of the two fast neutron detectors to discriminate between neutrons and gamma-rays were investigated. The NE-213 liquid-scintillator reference cell produced a wide range of scintillation-light yields in response to the gamma-ray field of the source. In stark contrast, the He4-based detector registered a maximum scintillation-light yield of 750 keVee to the same gamma-ray field. Pulse-shape discrimination for particles with scintillation-light yields of more than 750 keVee was excellent in the case of the He4-based detector, and above 750 keVee its signal was unambiguously neutron.

  12. Remark on the studies of the muon-induced neutron background in the liquid scintillator detectors

    OpenAIRE

    Zbiri, Karim

    2009-01-01

    This article gives a point of view on the studies of the muon-induced background for the underground experiments using a liquid scintillator detectors. The results obtained are in good agreement with the data, especially for the neutron yield production. This is the first time, when a study of this kind successes to get the same neutron yield as the one obtained from the experiment.

  13. Detection potential for the diffuse supernova neutrino background in the large liquid-scintillator detector LENA

    OpenAIRE

    Wurm, M.; F. von Feilitzsch; Goeger-Neff, M.; Hochmuth, K. A.; Undagoitia, T. Marrodan; Oberauer, L.; Potzel, W.

    2007-01-01

    The large-volume liquid-scintillator detector LENA (Low Energy Neutrino Astronomy) will provide high-grade background discrimination and enable the detection of diffuse supernova neutrinos (DSN) in an almost background-free energy window from ~10 to 25 MeV. Within ten years of exposure, it will be possible to derive significant constraints on both core-collapse supernova models and the supernova rate in the near universe up to redshifts z

  14. Scintillation detectors with multilayer polymer mirror reflector based on giant birefringent optics

    International Nuclear Information System (INIS)

    The design of interference mirrors is presented with unprecedented performance if birefringence is on the order of the change of the in-plane refractive index between adjacent polymeric layers (giant birefringent optics, GBO). Such a mirror, with ≥ 98% reflectivity in the visible, the VM2000 film was used to upgrade the performance of the DIAMANT charged particle detector system built up from CsI(Tl) scintillators coupled to Si-pin photodiodes. (R.P.)

  15. A gas scintillation counter with imaging optics and large area UV-detector

    Energy Technology Data Exchange (ETDEWEB)

    Nickles, J. E-mail: nickles@hsb.uni-frankfurt.de; Braeuning, H.; Braeuning-Demian, A.; Dangendorf, V.; Breskin, A.; Chechik, R.; Rauschnabel, K.; Schmidt-Boecking, H

    2002-01-21

    We report on the improvements in the position sensitive readout of a xenon-filled gas scintillation proportional counter. Using an imaging optic for UV-light in the region of 170 nm, the position resolution could be improved by more than 30%. In addition, we have obtained first encouraging results for the use of the recently developed gas electron multiplier together with a CsI-photocathode as a large area UV-detector system.

  16. A gas scintillation counter with imaging optics and large area UV-detector

    CERN Document Server

    Nickles, J; Bräuning-Demian, A; Breskin, Amos; Chechik, R; Dangendorf, V; Rauschnabel, K; Schmidt-Böcking, H

    2002-01-01

    We report on the improvements in the position sensitive readout of a xenon-filled gas scintillation proportional counter. Using an imaging optic for UV-light in the region of 170 nm, the position resolution could be improved by more than 30%. In addition, we have obtained first encouraging results for the use of the recently developed gas electron multiplier together with a CsI-photocathode as a large area UV-detector system.

  17. New submillimeter detectors and antenna arrays

    International Nuclear Information System (INIS)

    Preliminary investigation has been made into the use of SIS (superconductor--insulator--superconductor) diodes for possible roles in sub-millimeter imaging systems. That is, extremely low noise, millimeter wave detectors and mixers have recently been reported which depend on single-particle tunnelling between two superconducting films separated by a thin oxide layer. The combination of excellent low-frequency sensitivity and well-developed fabrication technology make the SIS mixers particularly attractive for the systems using antenna structures and arrays in millimeter and submillimeter regions. The SIS diodes of Nb-Nb2O5-Pb showed a strong video response to the radiation which could be differentiated from the regular Josephson effect since it was not affected by a magnetic field. In exploring the three-terminal devices for possible detector and source applications in submillimeter region, the authors first determined that millimeter and submillimeter radiation could be effectively coupled to and detected in high-frequency FETs. Video response was readily obtained at 800 GHz, and carcinotron radiation at 350 GHz was mixed with the 5th harmonic of a 70 GHz klystron, producing over 45 db signal-to-noise ratio in the intermediate frequency. Since FET can function as a three-terminal oscillator simultaneously detecting submillimeter radiation or optical beats, it has interesting possibility, such as self-oscillating mixers or subharmonic local oscillators. (Wakatsuki, Y.)

  18. Monte Carlo simulation of the data acquisition chain of scintillation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Binda, F.; Ericsson, G.; Hellesen, C.; Hjalmarsson, A.; Eriksson, J.; Skiba, M.; Conroy, S.; Weiszflog, M. [Uppsala University, Department of Physics and Astronomy, Division of Applied Nuclear Physics, 75120 Uppsala (Sweden)

    2014-08-21

    The good performance of a detector can be strongly affected by the instrumentation used to acquire the data. The possibility of anticipating how the acquisition chain will affect the signal can help in finding the best solution among different set-ups. In this work we developed a Monte Carlo code that aims to simulate the effect of the various components of a digital Data Acquisition system (DAQ) applied to scintillation detectors. The components included in the model are: the scintillator, the photomultiplier tube (PMT), the signal cable and the digitizer. We benchmarked the code against real data acquired with a NE213 scintillator, comparing simulated and real signal pulses induced by gamma-ray interaction. Then we studied the dependence of the energy resolution of a pulse height spectrum (PHS) on the sampling frequency and the bit resolution of the digitizer. We found that exceeding some values of the sampling frequency and the bit resolution improves only marginally the performance of the system. The method can be applied for the study of various detector systems relevant for nuclear techniques, such as in fusion diagnostics.

  19. Characterization of a scintillating fibers read by MPPC detectors trigger prototype for the AMADEUS experiment

    Science.gov (United States)

    Bazzi, M.; Berucci, C.; Curceanu, C.; D'Uffizi, A.; Piscicchia, K.; Poli Lener, M.; Romero Vidal, A.; Sbardella, E.; Scordo, A.; Vazquez Doce, O.

    2013-05-01

    Multi-Pixel Photon Counters (MPPC) consist of hundreds of micro silicon Avalanche PhotoDiodes (APD) working in Geiger mode. The high gain and the low noise, typical of these devices, together with their good performance in magnetic field, make them ideal readout detectors for scintillating fibers as trigger detectors in particle and nuclear physics experiments like AMADEUS, where such detectors are planned to be used to trigger on charged kaon pairs. In order to investigate the detection efficiency of such a system, a prototype setup consisting of 32, 1 mm diameter scintillating fibers, arranged in two double layers of 16 fibers each, and read out at both sides by 64 MPPCs with an ad-hoc built readout electronics, was tested at the πM-1 line of the Paul Scherrer Institute (PSI) in Villigen, Switzerland. The detection efficiency and the trigger capability were measured on a beam containing protons, electrons, muons and pions with a momentum of 440 MeV/c. The measured average efficiency for protons for a double layer of scintillating fibers (96.2±1.0%) represents a guarantee of the good performance of this system as a trigger for the AMADEUS experiment.

  20. Electronics design of a PET detector module with APD array

    CERN Document Server

    Wang Yong

    2002-01-01

    The author summarizes the advantages of APD-array for using in PET scanner. The front-end electronics for an experimental APD detector module was built and tested. According to the characteristics of APD-array and the demands of the signal readout in PET scanner, the full electronics system of an APD detector module was designed and presented in detail

  1. The Impact of Array Detectors on Raman Spectroscopy

    Science.gov (United States)

    Denson, Stephen C.; Pommier, Carolyn J. S.; Denton, M. Bonner

    2007-01-01

    The impact of array detectors in the field of Raman spectroscopy and all low-light-level spectroscopic techniques is examined. The high sensitivity of array detectors has allowed Raman spectroscopy to be used to detect compounds at part per million concentrations and to perform Raman analyses at advantageous wavelengths.

  2. Position sensitivity of MAMA detectors. [Multi-Anode Microchannel Array

    Science.gov (United States)

    Morgan, J. S.; Slater, D. S.; Timothy, J. G.; Jenkins, E. B.

    1988-01-01

    The results of laboratory and telescopic measurements of the position sensitivity of a visible MAMA detector utilizing a 'coarse-fine' array are presented. The photometric accuracy of this detector was determined under point source illumination. It was found that computed centroid positions are accurate across the entire array to within 0.04 pixels.

  3. A large dynamic range readout design for the plastic scintillator detector of DAMPE

    Science.gov (United States)

    Zhou, Yong; Sun, Zhiyu; Yu, Yuhong; Zhang, Yongjie; Fang, Fang; Chen, Junling; Hu, Bitao

    2016-08-01

    A large dynamic range is required by the Plastic Scintillator Detector (PSD) of DArk Matter Particle Explorer (DAMPE) to detect particles from electron to heavy ions with Z ≤ 20. To expand the dynamic range, the readout design based on the double-dynodes signal extraction from the photomultiplier tube has been proposed and adopted by PSD. To verify this design, a prototype detector module has been constructed and tested with cosmic ray and relativistic ion beam. The results match with the estimation and the readout unit could easily cover the required dynamic range of about 4 orders of magnitude.

  4. Systematic approach to on-line calibration of the scintillation detectors of GRAPES-3 experiment

    International Nuclear Information System (INIS)

    The observable characteristics of extensive air showers provide indirect information on two important areas of high energy physics and astrophysics, namely, some characteristics of particle interactions in the very forward region and the energy spectra and relative flux of various nuclear groups present in the primary cosmic rays, at ultra-high energies. These information 's are obtained from the nuclear detectors after their output passes through systems which alter their forms to interpret the information required. The detailed description of the calibration system is given below. This on-line calibration is done for all the 400 plus scintillation detectors by ROOT software package

  5. Determination of the time resolution for neutron scintillation detectors by multi-coincidence measurement

    Institute of Scientific and Technical Information of China (English)

    LI Yong-Ming; RUAN Xi-Chao; ZHOU Sin; MA Zhong-Yuan

    2011-01-01

    Based on the multi-coincidence measurement, the time resolution of three liquid scintillation detectors (BC501A) were determined strictly by solving the coincidence equations, where the influence from electronics estimated by self coincidence measurement as well as the background had been considered. The result of this work agreed well with the result that was deduced from the traditional method, and it will be helpful to analyze the energy resolution of neutron time of flight spectra measured by using such detectors at CIAE (China Institute of Atomic Energy).

  6. R&D on scintillation materials for novel ionizing radiation detectors for High Energy Physics, medical imaging and industrial applications

    CERN Multimedia

    Hillemanns, H; Chipaux, R; Vasilev, A; Rinaldi, D; Martinez turtos, R; Pizzichemi, M; Morel, C; Choi, Y

    2002-01-01

    The Crystal Clear Collaboration (CCC) was approved by the Detector R&D Committee as RD18 in 1990 with the objective of developing new inorganic scintillators suitable for crystal electromagnetic calorimeters of LHC experiments. From 1990 to 1994, CCC made an intensive investigation for the quest of the most adequate ideal scintillator for the LHC; three main candidates were identified and extensively studied : CeF$_{3}$, PbWO$_{4}$ and heavy scintillating glasses. Lead tungstate was chosen by CMS and ALICE as the most cost effective crystal compliant to LHC conditions. Today 76648 PWO crystals are installed in CMS and 17920 in ALICE. After this success Crystal clear has continued its investigation on new scintillators and the understanding of scintillation mechanisms and light transfer properties in particular : The understanding of cerium ion as activator, The development of LuAP, LuYAP crystals for medical imaging applications, (CERN patent) Investigation of Ytterbium based scintillators for solar ne...

  7. Plastic scintillation detectors for precision time-of-flight measurements of relativistic heavy ions

    CERN Document Server

    Lin, Wen-Jian; Sun, Bao-Hua; He, Liu-Chun; Lin, Wei-Ping; Liu, Chuan-Ye; Tanihata, Isao; Terashima, Satoru; Tian, Yi; Wang, Feng; Wang, Meng; Zhang, Guang-Xin; Zhang, Xue-Heng; Zhu, Li-Hua; Duan, Li-Min; Hu, Rong-Jiang; Liu, Zhong; Lu, Chen-Gui; Ren, Pei-Pei; Sheng, Li-Na; Sun, Zhi-Yu; Wang, Shi-Tao; Wang, Tao-Feng; Xu, Zhi-Guo; Yan, Duo; Yue, Ke; Zheng, Yong

    2016-01-01

    Plastic scintillation detectors for Time-of-Flight (TOF) measurements are almost essential for event-by-event identification of relativistic rare isotopes. In this work, a pair of plastic scintillation detectors of 50 $\\times$ 50 $\\times$ 3$^{t}$ mm$^3$ and 80 $\\times$ 100 $\\times$ 3$^{t}$ mm$^3$ have been set up at the external target facility (ETF), Institute of Modern Physics. Their time, energy and position responses are measured with $^{18}$O primary beam at 400 MeV/nucleon. After the off-line walk-effect and position corrections, the time resolution of the two detectors are determined to be 27 ps ($\\sigma$) and 36 ps ($\\sigma$), respectively. Both detectors have nearly the same energy resolution of 3$\\%$ ($\\sigma$) and position resolution of 2 mm ($\\sigma$). The detectors have been used successfully in nuclear reaction cross section measurements, and will be be employed for upgrading RIBLL2 beam line at IMP as well as for the high energy branch at HIAF.

  8. Design Constraints for a WIMP Dark Matter and pp Solar Neutrino Liquid Neon Scintillation Detector

    CERN Document Server

    Boulay, M G; Lidgard, J

    2004-01-01

    Detailed Monte-Carlo simulations were used to evaluate the performance of a liquid neon scintillation detector for dark matter and low-energy solar neutrino interactions. A maximum-likelihood event vertex fitter including PMT time information was developed, which significantly improves position resolution over spatial-only algorithms, and substantially decreases the required detector size and achievable analysis energy threshold. The ultimate sensitivity to WIMP dark matter and the pp flux uncertainty are evaluated as a function of detector size. The dependence on the neon scintillation and PMT properties are evaluated. A 300 cm radius detector would allow a ~13 keV threshold, a pp flux uncertainty of ~1%, and limits on the spin-independent WIMP-nucleon cross-section of ~10^{-46} cm^2 for a 100 GeV WIMP, using commercially available PMTs. Detector response calibration and background requirements for a precision pp measurement are defined. Internal radioactivity requirements for uranium, thorium, and krypton a...

  9. A scintillating bolometer array for double beta decay studies: The LUCIFER experiment

    Science.gov (United States)

    Gironi, L.

    2016-07-01

    The main goal of the LUCIFER experiment is to study the neutrinoless double beta decay, a rare process allowed if neutrinos are Majorana particles. Although aiming at a discovery, in the case of insufficient sensitivity the LUCIFER technique will be the demonstrator for a higher mass experiment able to probe the entire inverted hierarchy region of the neutrino mass. In order to achieve this challenging result, high resolution detectors with active background discrimination capability are required. This very interesting possibility can be largely fulfilled by scintillating bolometers thanks to the simultaneous read-out of heat and light emitted by the interactions in the detector or by pulse shape analysis.

  10. Development and characterization of scintillation based detectors for the use in radiological early warning networks

    Science.gov (United States)

    Kessler, P.; Dombrowski, H.; Neumaier, S.

    2016-02-01

    To detect radiological incidents, all members of the European Union have installed nationwide radiological early warning networks. Most of the installed detector systems supply only dosimetric information. Novel spectrometry systems are considered to be good candidates for a new detector generation for environmental radiation monitoring because they will supply both nuclide-specific information and ambient dose equivalent rate values. Four different detector types were chosen and compared with each other (LaBr3, CeBr3, SrI2 scintillation detectors, and CdZnTe, a semiconductor detector). As a first step, the inherent background of these detectors was measured in the low background underground laboratory UDO II of PTB. As a second step, the relative detection sensitivity between the various detectors was determined at different energies. Finally, the detectors were exposed to a 4π-radiation field of radon progeny in PTB's radon chamber. The obtained results show that the investigated detectors are well suited for environmental radiation monitoring.

  11. Development and characterization of scintillation based detectors for the use in radiological early warning networks

    International Nuclear Information System (INIS)

    To detect radiological incidents, all members of the European Union have installed nationwide radiological early warning networks. Most of the installed detector systems supply only dosimetric information. Novel spectrometry systems are considered to be good candidates for a new detector generation for environmental radiation monitoring because they will supply both nuclide-specific information and ambient dose equivalent rate values. Four different detector types were chosen and compared with each other (LaBr3, CeBr3, SrI2 scintillation detectors, and CdZnTe, a semiconductor detector). As a first step, the inherent background of these detectors was measured in the low background underground laboratory UDO II of PTB. As a second step, the relative detection sensitivity between the various detectors was determined at different energies. Finally, the detectors were exposed to a 4π-radiation field of radon progeny in PTB's radon chamber. The obtained results show that the investigated detectors are well suited for environmental radiation monitoring

  12. Conceptual design of the early implementation of the NEutron Detector Array (NEDA) with AGATA

    International Nuclear Information System (INIS)

    The NEutron Detector Array (NEDA) project aims at the construction of a new high-efficiency compact neutron detector array to be coupled with large γ -ray arrays such as AGATA. The application of NEDA ranges from its use as selective neutron multiplicity filter for fusion-evaporation reaction to a large solid angle neutron tagging device. In the present work, possible configurations for the NEDA coupled with the Neutron Wall for the early implementation with AGATA has been simulated, using Monte Carlo techniques, in order to evaluate their performance figures. The goal of this early NEDA implementation is to improve, with respect to previous instruments, efficiency and capability to select multiplicity for fusion-evaporation reaction channels in which 1, 2 or 3 neutrons are emitted. Each NEDA detector unit has the shape of a regular hexagonal prism with a volume of about 3.23l and it is filled with the EJ301 liquid scintillator, that presents good neutron- γ discrimination properties. The simulations have been performed using a fusion-evaporation event generator that has been validated with a set of experimental data obtained in the 58Ni + 56Fe reaction measured with the Neutron Wall detector array. (orig.)

  13. Conceptual design of the early implementation of the NEutron Detector Array (NEDA) with AGATA

    Energy Technology Data Exchange (ETDEWEB)

    Hueyuek, Tayfun; Gadea, Andres; Domingo-Pardo, Cesar [Universidad de Valencia, Instituto de Fisica Corpuscular, CSIC, Paterna (Valencia) (Spain); Di Nitto, Antonio [Istituto Nazionale di Fisica Nucleare, Napoli (Italy); Johannes Gutenberg-Universitaet Mainz, Mainz (Germany); Jaworski, Grzegorz; Javier Valiente-Dobon, Jose; De Angelis, Giacomo; Modamio, Victor; Triossi, Andrea [Laboratori Nazionali di Legnaro, Istituto Nazionale di Fisica Nucleare, Legnaro (Italy); Nyberg, Johan [Uppsala University, Department of Physics and Astronomy, Uppsala (Sweden); Palacz, Marcin [University of Warsaw, Heavy Ion Laboratory, Warsaw (Poland); Soederstroem, Paer-Anders [RIKEN Nishina Center, Saitama (Japan); Aliaga-Varea, Ramon Jose [Universidad de Valencia, Instituto de Fisica Corpuscular, CSIC, Paterna (Valencia) (Spain); Universidad Politecnica de Valencia, I3M, Valencia (Spain); Atac, Ayse [Ankara University, Department of Physics, Faculty of Sciences, Ankara (Turkey); The Royal Institute of Technology, Stockholm (Sweden); Collado, Javier; Egea, Francisco Javier; Gonzalez, Vicente; Sanchis, Enrique [University of Valencia, Department of Electronic Engineering, Burjassot (Valencia) (Spain); Erduran, Nizamettin [Istanbul Sabahattin Zaim University, Faculty of Engineering and Natural Sciences, Istanbul (Turkey); Ertuerk, Sefa [University of Nigde, Department of Physics, Faculty of Science and Arts, Nigde (Turkey); France, Gilles de [CNRS/IN2P3, GANIL, CEA/DSAM, Caen (France); Gadea, Rafael; Herrero-Bosch, Vicente [Universidad Politecnica de Valencia, I3M, Valencia (Spain); Kaskas, Ayse [Ankara University, Department of Physics, Faculty of Sciences, Ankara (Turkey); Moszynski, Marek [National Centre for Nuclear Research, Otwock-Swierk (Poland); Wadsworth, Robert [University of York, Department of Physics, York (United Kingdom)

    2016-03-15

    The NEutron Detector Array (NEDA) project aims at the construction of a new high-efficiency compact neutron detector array to be coupled with large γ -ray arrays such as AGATA. The application of NEDA ranges from its use as selective neutron multiplicity filter for fusion-evaporation reaction to a large solid angle neutron tagging device. In the present work, possible configurations for the NEDA coupled with the Neutron Wall for the early implementation with AGATA has been simulated, using Monte Carlo techniques, in order to evaluate their performance figures. The goal of this early NEDA implementation is to improve, with respect to previous instruments, efficiency and capability to select multiplicity for fusion-evaporation reaction channels in which 1, 2 or 3 neutrons are emitted. Each NEDA detector unit has the shape of a regular hexagonal prism with a volume of about 3.23l and it is filled with the EJ301 liquid scintillator, that presents good neutron- γ discrimination properties. The simulations have been performed using a fusion-evaporation event generator that has been validated with a set of experimental data obtained in the {sup 58}Ni + {sup 56}Fe reaction measured with the Neutron Wall detector array. (orig.)

  14. New application of scintillator ZnSe(Te) in scintielectronic detectors for detection of neutrons, medical imaging, explosive detection, and NDT

    Science.gov (United States)

    Ryzhikov, Volodymyr D.; Opolonin, Oleksandr D.; Fedorov, Alexander G.; Lysetska, Olena K.; Kostioukevitch, Sergey A.

    2008-08-01

    Scintillators on the basis of AIIBVI compounds, such as ZnSe(Te), can be used for detection of secondary charged particles coming from nuclear reactions in which neutrons interact with target nuclei of atoms present in transparent materials of dispersion scintillation detectors matrices. Using unique properties of scintillator ZnSe(Te) we show possibility of increase detection efficiency for soft x-ray radiation (20 - 90 keV). The amorphous silicon flat panels and the photodiode arrays wide used for non-destructive testing and medical imaging (spatial resolution 20 - 400 mkm). By our estimations, using of such detectors in combination with thin film of ZnSe(Te) can increase efficiency of registration of x-ray radiation (for the source of 60-140kV) in 1,2 - 2 times. We obtained thin films (10-450mkm) of scintillator ZnSe(Te) on the different substrate materials and estimated the relative light yield of the layers deposited on the graphite and Al2O3 ceramic substrates and the bulk ZnSe(Te) crystal. Use of ZnSe(Te) in the low-energy "scintillator - photodiode" type detector allowed to increase accuracy of authentication of explosives (HEIMANN X-RAY INSPECTION SYSTEM EDtS10080). Using the dual energy digital radiography system prototype we obtained the x-ray images (60 projections of each object). These images are basic data for computer tomography and three-dimensional reconstruction of density and effective atomic number. The color identification palette provides clearly show variations of effective atomic number in biological and inorganic objects. So, for example, changes of calcium concentration in a bone. The research described in this publication was supported by STCU #4115 and NATO SfP-982823.

  15. Characterization of a scintillating lithium glass ultra-cold neutron detector

    CERN Document Server

    Jamieson, Blair; Hansen-Romu, Sean; Lauss, Bernhard; Lindner, Thomas; Martin, Jeffery W; Pierre, Edgard

    2016-01-01

    A new 6-Li glass based scintillation detector developed for the TRIUMF neutron electric dipole moment experiment was characterized using the ultra-cold neutron source at the Paul Scherrer Institute (PSI). The data acquisition system for this new detector was demonstrated to perform well at rejecting backgrounds. An estimate of the absolute efficiency of background rejection is made as a function of rate. For the variable ultra-cold neutron rate, varying from approx 1 kHz to 100 kHz per channel, and background rate seen at the Paul Scherrer Institut, we estimate that the absolute detector efficiency is 89.7+1.3-1.9 % and the background contamination is 0.3 +- 0.1 %. Finally a comparison with a commercial Cascade detector was performed for a specific setup at the West-2 beamline of the ultra-cold neutron source at PSI.

  16. Development of Yangbajing Air shower Core detector array for a new EAS hybrid Experiment

    CERN Document Server

    Liu, Jinsheng; Chen, Ding; Zhang, Ying; Zhai, Liuming; Chen, Xu; Hu, Xiaobin; Lin, Yuhui; Zhang, Xueyao; Feng, Cunfeng; Jia, Huanyu; Zhou, Xunxiu; DanZengLuoBu,; Chen, Tianlu; Li, Haijin; Liu, Maoyuan; Yuan, Aifang

    2015-01-01

    Aiming at the observation of cosmic-ray chemical composition at the "knee" energy region, we have been developinga new type air-shower core detector (YAC, Yangbajing Air shower Core detector array) to be set up at Yangbajing (90.522$^\\circ$ E, 30.102$^\\circ$ N, 4300 m above sea level, atmospheric depth: 606 g/m$^2$) in Tibet, China. YAC works together with the Tibet air-shower array (Tibet-III) and an underground water cherenkov muon detector array (MD) as a hybrid experiment. Each YAC detector unit consists of lead plates of 3.5 cm thick and a scintillation counter which detects the burst size induced by high energy particles in the air-shower cores. The burst size can be measured from 1 MIP (Minimum Ionization Particle) to $10^{6}$ MIPs. The first phase of this experiment, named "YAC-I", consists of 16 YAC detectors each having the size 40 cm $\\times$ 50 cm and distributing in a grid with an effective area of 10 m$^{2}$. YAC-I is used to check hadronic interaction models. The second phase of the experiment,...

  17. Multi-Channel Detector Arrays for Heavy Ion Beam Probes

    Science.gov (United States)

    Aceto, Steven; Beckstead, Jeffrey; Castracane, James; Iguchi, H.; Fujisawa, A.; Demers, Diane; Schatz, John

    1997-11-01

    InterScience, Inc. has developed a multiple slit detector array for use with heavy ion beam probes. The first array was a twenty element array installed on the TEXT tokamak. An initial set of data was obtained with this array prior to the shutdown on the TEXT tokamak in December of 1995. More recently, a smaller detector array has been developed for use in the CHS torsatron in Nagoya. This array is smaller than the TEXT array, with ten elements, but contains two prototype sets of detector plates to determine the beam position. The operating conditions in CHS are expected to be much harsher than in TEXT, with ECH and NBI plasmas. Trajectory simulations allowed for the design of a tilted detector array in the CHS vacuum vessel. First tests of the CHS array will begin in the late summer of 1997. Other candidate machines for detector arrays are the MST reversed field pinch, in which a beam probe is expected to be installed in late 1997 or early 1998 and the Large Helical Device (LHD) which is expected to be operational in 1998. Design issues, trajectory simulations and array test results will be presented. Supported in part by the U.S. Department of Energy under Grant #DE-FG02-94ER81788

  18. High spatial resolution radiation detectors based on hydrogenated amorphous silicon and scintillator

    International Nuclear Information System (INIS)

    Hydrogenated amorphous silicon (a-Si:H) as a large-area thin film semiconductor with ease of doping and low-cost fabrication capability has given a new impetus to the field of imaging sensors; its high radiation resistance also makes it a good material for radiation detectors. In addition, large-area microelectronics based on a-Si:H or polysilicon can be made with full integration of peripheral circuits, including readout switches and shift registers on the same substrate. Thin a-Si:H p-i-n photodiodes coupled to suitable scintillators are shown to be suitable for detecting charged particles, electrons, and X-rays. The response speed of CsI/a-Si:H diode combinations to individual particulate radiation is limited by the scintillation light decay since the charge collection time of the diode is very short (< 10ns). The reverse current of the detector is analyzed in term of contact injection, thermal generation, field enhanced emission (Poole-Frenkel effect), and edge leakage. A good collection efficiency for a diode is obtained by optimizing the p layer of the diode thickness and composition. The CsI(Tl) scintillator coupled to an a-Si:H photodiode detector shows a capability for detecting minimum ionizing particles with S/N ∼20. In such an arrangement a p-i-n diode is operated in a photovoltaic mode (reverse bias). In addition, a p-i-n diode can also work as a photoconductor under forward bias and produces a gain yield of 3--8 for shaping times of 1 micros. The mechanism of the formation of structured CsI scintillator layers is analyzed. Initial nucleation in the deposited layer is sensitive to the type of substrate medium, with imperfections generally catalyzing nucleation. Therefore, the microgeometry of a patterned substrate has a significant effect on the structure of the CsI growth

  19. Structured scintillators for X-ray imaging with micrometre resolution

    DEFF Research Database (Denmark)

    Olsen, Ulrik Lund; Schmidt, Søren; Poulsen, Henning Friis;

    2009-01-01

    A 3D X-ray detector for imaging of 30–200 keV photons is described. It comprises a stack of semitransparent structured scintillators, where each scintillator is a regular array of waveguides in silicon, and with pores filled with CsI. The performance of the detector is described theoretically...

  20. Conceptual design and optimization of a plastic scintillator array for 2D tomography using a compact D–D fast neutron generator

    International Nuclear Information System (INIS)

    A conceptual design optimization of a fast neutron tomography system was performed. The system is based on a compact deuterium–deuterium fast neutron generator and an arc-shaped array of individual neutron detectors. The array functions as a position sensitive one-dimensional detector allowing tomographic reconstruction of a two-dimensional cross section of an object up to 10 cm across. Each individual detector is to be optically isolated and consists of a plastic scintillator and a Silicon Photomultiplier for measuring light produced by recoil protons. A deterministic geometry-based model and a series of Monte Carlo simulations were used to optimize the design geometry parameters affecting the reconstructed image resolution. From this, it is expected that with an array of 100 detectors a reconstructed image resolution of ∼1.5 mm can be obtained. Other simulations were performed in order to optimize the scintillator depth (length along the neutron path) such that the best ratio of direct to scattered neutron counts is achieved. This resulted in a depth of 6–8 cm and an expected detection efficiency of 33–37%. Based on current operational capabilities of a prototype neutron generator being developed at the Paul Scherrer Institute, planned implementation of this detector array design should allow reconstructed tomograms to be obtained with exposure times on the order of a few hours. - Highlights: • Conceptual design and optimization of a 2D fast neutron tomography system were performed. • Monte Carlo simulations were used to estimate ∼1.5 mm resolution and negligible scattering effects. • Geometry-based deterministic model was developed and used to verify the Monte Carlo results

  1. The neutron detectors based on oxide scintillators for control of fissionable radioactive substances

    Science.gov (United States)

    Ryzhikov, V. D.; Grinyov, B. V.; Onyshchenko, G. M.; Piven, L. A.; Lysetska, O. K.; Opolonin, O. D.; Kostioukevitch, S. A.; Smith, C. F.

    2014-09-01

    A large-area X-ray CMOS image sensor (LXCIS) is widely used in mammography, non-destructive inspection, and animal CT. For LXCIS, in spite of weakness such as low spatial and energy resolution, a Indirect method using scintillator like CsI(Tl) or Gd2O2S is still well-used because of low cost and easy manufacture. A photo-diode for X-ray imaging has large area about 50 ~ 200 um as compared with vision image sensors. That is because X-ray has feature of straight and very small light emission of a scintillator. Moreover, notwithstanding several structure like columnar, the scintillator still emit a diffusible light. This diffusible light from scintillator can make spatial crosstalk in X-ray photodiode array because of a large incidence angle. Moreover, comparing with vision image sensors, X-ray sensor doesn't have micro lens for gathering the photons to photo-diode. In this study, we simulated the affection of spatial crosstalk in X-ray sensor by comparing optical sensor. Additionally, the chip, which was fabricated in 0.18 um 1P5M process by Hynix in Korea, was tested to know the effect of spatial crosstalk by changing design parameters. From these works, we found out that spatial crosstalk is affected by pixel pitch, incident angle of photons, and micro lens on each pixels.

  2. Concept for a magnetic monopole detector using liquid scintillator

    International Nuclear Information System (INIS)

    This paper is a description of a new concept for a magnetic monopole detector and a laboratory report of experimental results from a realized version of the concept. There have been no previous tests using this concept although a good number of searches for monopoles have been carried out in the past. Several of these searches are similar to the one in this paper and will be reviewed therein. All of the work for this paper, including all testing and experimentation, was done at Brown University in a lab operated by the High Energy Group here. The particle sources for the experiment were random cosmic rays and the Big Bang (for relic magnetic monopoles). The goal of the experiment is to search for relic magnetic monopoles, or, if none are found, to at least set a flux limit on them. All the work was conducted between December 1982 and June 1983 as a Senior Thesis independent research project. The work centered around testing the equipment and constructing a proper triggering mechanism and, therefore, does not emphasize the theoretical aspects. The theory behind magnetic monopoles from 1896 to present and past experimental searches are summarized

  3. An experimental study of antireflective coatings in Ge light detectors for scintillating bolometers

    Directory of Open Access Journals (Sweden)

    Mancuso M.

    2014-01-01

    Full Text Available Luminescent bolometers are double-readout devices able to measure simultaneously the phonon and the light yields after a particle interaction in the detector. This operation allows in some cases to tag the type of the interacting quantum, crucial issue for background control in rare event experiments such as the search for neutrinoless double beta decay and for interactions of particle dark matter candidates. The light detectors used in the LUCIFER and LUMINEU searches (projects aiming at the study of the double beta interesting candidates 82Se and 100Mo using ZnSe and ZnMoO4 scintillating bolometers consist of hyper-pure Ge thin slabs equipped with NTD thermistors. A substantial sensitivity improvement of the Ge light detectors can be obtained applying a proper anti-reflective coatings on the Ge side exposed to the luminescent bolometer. The present paper deals with the investigation of this aspect, proving and quantifying the positive effect of a SiO2 and a SiO coating and setting the experimental bases for future tests of other coating materials. The results confirm that an appropriate coating procedure helps in improving the sensitivity of bolometric light detectors by an important factor (in the range 20% – 35% and needs to be included in the recipe for the development of an optimized radio-pure scintillating bolometer.

  4. A directional fast neutron detector using scintillating fibers and an intensified CCD camera system

    International Nuclear Information System (INIS)

    We have been developing and testing a scintillating fiber detector (SFD) for use as a fast neutron sensor which can discriminate against neutrons entering at angles non-parallel to the fiber axis (''directionality''). The detector/convertor component is a fiber bundle constructed of plastic scintillating fibers each measuring 10 cm long and either 0.3 mm or 0.5 mm in diameter. Extensive Monte Carlo simulations were made to optimize the bundle response to a range of fast neutron energies and to intense fluxes of high energy gamma-rays. The bundle is coupled to a set of gamma-ray insenitive electro-optic intensifiers whose output is viewed by a CCD camera directly coupled to the intensifiers. Two types of CCD cameras were utilized: 1) a standard, interline RS-170 camera with electronic shuttering and 2) a high-speed (up to 850 frame/s) field-transfer camera. Measurements of the neutron detection efficiency and directionality were made using 14 MeV neutrons, and the response to gamma-rays was performed using intense fluxes from radioisotopic sources (up to 20 R/h). Recently, the detector was constructed and tested using a large 10 cm by 10 cm square fiber bundle coupled to a 10 cm diameter GEN I intensifier tube. We present a description of the various detector systems and report the results of experimental tests. ((orig.))

  5. Triton burnup study using scintillating fiber detector on JT-60U

    Energy Technology Data Exchange (ETDEWEB)

    Harano, Hideki [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    1997-09-01

    The DT fusion reactor cannot be realized without knowing how the fusion-produced 3.5 MeV {alpha} particles behave. The {alpha} particles` behavior can be simulated using the 1 MeV triton. To investigate the 1 MeV triton`s behavior, a new type of directional 14 MeV neutron detector, scintillating fiber (Sci-Fi) detector has been developed and installed on JT-60U in the cooperation with LANL as part of a US-Japan collaboration. The most remarkable feature of the Sci-Fi detector is that the plastic scintillating fibers are employed for the neutron sensor head. The Sci-Fi detector measures and extracts the DT neutrons from the fusion radiation field in high time resolution (10 ms) and wide dynamic range (3 decades). Triton burnup analysis code TBURN has been made in order to analyze the time evolution of DT neutron emission rate obtained by the Sci-Fi detector. The TBURN calculations reproduced the measurements fairly well, and the validity of the calculation model that the slowing down of the 1 MeV triton was classical was confirmed. The Sci-Fi detector`s directionality indicated the tendency that the DT neutron emission profile became more and more peaked with the time progress. In this study, in order to examine the effect of the toroidal field ripple on the triton burnup, R{sub p}-scan and n{sub e}-scan experiments have been performed. The R{sub p}-scan experiment indicates that the triton`s transport was increased as the ripple amplitude over the triton became larger. In the n{sub e}-scan experiment, the DT neutron emission showed the characteristic changes after the gas puffing injection. It was theoretically confirmed that the gas puffing was effective for the collisionality scan. (J.P.N.) 127 refs.

  6. Four-layer DOI PET detectors using a multi-pixel photon counter array and the light sharing method

    Energy Technology Data Exchange (ETDEWEB)

    Nishikido, Fumihiko, E-mail: funis@nirs.go.jp; Inadama, Naoko; Yoshida, Eiji; Murayama, Hideo; Yamaya, Taiga

    2013-11-21

    Silicon photomultipliers (SiPMs) provide many advantages for PET detectors, such as their high internal gain, high photon detection efficiency and insensitivity to magnetic fields. The number of detectable scintillation photons of SiPMs, however, is limited by the number of microcells. Therefore, pulse height of PET detectors using SiPMs is saturated when large numbers of scintillation photons enter the SiPM pixels. On the other hand, we previously presented a depth-of-interaction (DOI) encoding method that is based on the light sharing method. Since our encoding method detects scintillation photons with multiple readout pixels, the saturation effect can be suppressed. We constructed two prototype four-layer DOI detectors using a SiPM array and evaluated their performances. The two prototype detectors consisted of four layers of a 6×6 array of Lu{sub 2(1−x)}Y{sub 2x}SiO{sub 5} (LYSO) crystals and a SiPM (multi-pixel photon detector, MPPC, Hamamatsu Photonics K.K.) array of 4×4 pixels. The size of each LYSO crystal element was 1.46 mm×1.46 mm×4.5 mm and all surfaces of the crystal elements were chemically etched. We used two types of MPPCs. The first one had 3600 microcells and high photon detection efficiency (PDE). The other one had 14,400 microcells and lower PDE. In the evaluation experiment, all the crystals of the detector using the MPPC which had the high PDE were clearly identified. The respective energy and timing resolutions of lower than 15% and 1.0 ns were achieved for each crystal element. No saturation of output signals was observed in the 511 keV energy region due to suppression of the saturation effect by detecting scintillation photons with several MPPC pixels by the light sharing method. -- Highlights: •We constructed and evaluated four-layer DOI detectors by the light sharing method using a MPPC array. •The detectors using two types of the MPPC array were compared. •The energy and timing resolutions of lower than 15% and 1.0 ns were

  7. Differentiation method for localization of Compton edge in organic scintillation detectors

    CERN Document Server

    Safari, M J; Afarideh, H

    2016-01-01

    This paper, presents a simple method for accurate calibration of organic scintillation detectors. The method is based on the fact that differentiating the response function leads to accurate estimation of the Compton edge. The differentiation method in addition to the location of the Compton edge, gives insights into the parameters of the folded Gaussian function which is useful for determination of the energy resolution. Moreover, it is observed that the uncorrelated noise in the measurement of the response function does not impose significant uncertainties in the evaluations. By simulation of the bounded electrons and considering the Doppler effects, we are able to calculate a first estimation for the intrinsic Doppler resolution of a plastic scintillator, benefiting from the capability of the differentiation method.

  8. Scalability, scintillation readout and charge drift in a kilogram scale solid xenon particle detector

    CERN Document Server

    Yoo, J; Jaskierny, W F; Markley, D; Pahlka, R B; Balakishiyeva, D; Saab, T; Filipenko, M

    2014-01-01

    We report a demonstration of the scalability of optically transparent xenon in the solid phase for use as a particle detector above a kilogram scale. We employ a liquid nitrogen cooled cryostat combined with a xenon purification and chiller system to measure the scintillation light output and electron drift speed from both the solid and liquid phases of xenon. Scintillation light output from sealed radioactive sources is measured by a set of high quantum efficiency photomultiplier tubes suitable for cryogenic applications. We observed a reduced amount of photons in solid phase compared to that in liquid phase. We used a conventional time projection chamber system to measure the electron drift time in a kilogram of solid xenon and observed faster electron drift speed in the solid phase xenon compared to that in the liquid phase.

  9. Scintillator Pad Detector: Very Front End Electronics. Design and Pre-Series

    Science.gov (United States)

    Luengo, S.; Riera, J.; Tortella, S.; Vilasis-Cardona, X.; Gascón, D.; Comerma, A.; Garrido, L.

    2006-10-01

    The SPD (Scintillator Pad Detector) is a part of LHCb calorimeter which is designed to distinguish electrons and photons for this first level trigger. This detector is a plastic scintillator layer, divided in about 6000 cells of different size to obtain better granularity near the beam. Charged particles will produce, and photons will not, ionisation on the scintillator. This ionisation generates a light pulse that is collected by a Wavelength Shifting (WLS) fibre that is twisted inside the scintillator cell. The light is transmitted through a clear fibre to the readout system. For cost reduction, these 6000 cells are divided in groups using a MAPMT of 64 channels for receiving information in the readout system. The signal outing the SPD PMTs is rather unpredictable as a result of the low photostatistics, 20-30 photoelectrons per MIP, and the response of the WLS fibre, which has low decay time. Then, the signal processing must be performed by first integrating the total charge and later subtracting to avoid pile-up. The SPD Readout system is performed by an ASIC which integrates the signal, makes the pile-up compensation, and compares the level obtained to a programmable threshold (distinguishing electrons and photons), an FPGA which programmes the ASIC thresholds and pile-up subtraction and finally LVDS serializers, in order to send information to the first level trigger system. The design of the VFE unit takes into account not only mechanical constraints, as a result of the little space for the readout electronics but also the radiation quote expected in the environment and the distance between the VFE electronics and the racks were information is sent.

  10. Reaching time resolution of less than 10 ps with plastic scintillation detectors

    Science.gov (United States)

    Zhao, J. W.; Sun, B. H.; Tanihata, I.; Terashima, S.; Zhu, L. H.; Enomoto, A.; Nagae, D.; Nishimura, T.; Omika, S.; Ozawa, A.; Takeuchi, Y.; Yamaguchi, T.

    2016-07-01

    Timing-pick up detectors with excellent timing resolutions are essential in many modern nuclear physics experiments. Aiming to develop a Time-Of-Flight system with precision down to about 10 ps, we have made a systematic study of the timing characteristic of TOF detectors, which consist of several combinations of plastic scintillators and photomultiplier tubes. With the conventional electronics, the best timing resolution of about 5.1 ps (σ) has been achieved for detectors with an area size of 3 × 1cm2 . It is found that for data digitalization a combination of TAC and ADC can achieve a better time resolution than the currently available TDC. Simultaneous measurements of both time and pulse height are very valuable for the correction of time-walk effect.

  11. High-pressure plastic scintillation detector for measuring radiogenic gases in flow systems

    CERN Document Server

    Schell, W R; Yoon, S R; Tobin, M J

    1999-01-01

    Radioactive gases are emitted into the atmosphere from nuclear electric power and nuclear fuel reprocessing plants, from hospitals discarding xenon used in diagnostic medicine, as well as from nuclear weapons tests. A high-pressure plastic scintillation detector was constructed to measure atmospheric levels of such radioactive gases by detecting the beta and internal conversion (IC) electron decays. Operational tests and calibrations were made that permit integration of the flow detectors into a portable Gas Analysis, Separation and Purification system (GASP). The equipment developed can be used for measuring fission gases released from nuclear reactor sources and/or as part of monitoring equipment for enforcing the Comprehensive Test Ban Treaty. The detector is being used routinely for in-line gas separation efficiency measurements, at the elevated operational pressures used for the high-pressure swing analysis system (2070 kPa) and at flow rates of 5-15 l/min . This paper presents the design features, opera...

  12. Development of a fast plastic scintillation detector with time resolution of less than 10 ps

    CERN Document Server

    Zhao, J W; Tanihata, I; Terashima, S; Zhu, L H; Enomoto, A; Nagae, D; Nishimura, T; Omika, S; Ozawa, A; Takeuchi, Y; Yamaguchi, T

    2016-01-01

    Timing-pick up detectors with excellent timing resolutions are essential in many modern nuclear physics experiments. Aiming to develop a Time-Of-Flight system with precision down to about 10 ps, we have made a systematic study of the timing characteristic of TOF detectors, which consist of several combinations of plastic scintillators and photomultiplier tubes. With the conventional electronics, the best timing resolution of about 5.1 ps ({\\sigma}) has been achieved for detectors with an area size of 3x1 cm2. It is found that for data digitalization a combination of TAC and ADC can achieve a better time resolution than currently available TDC. Simultaneously measurements of both time and pulse height are very valuable for correction of time-walk effect.

  13. Intraoperative tumour detection using 111In-DTPA-D-Phe1-octreotide and a scintillation detector

    International Nuclear Information System (INIS)

    Intraoperative tumour detection has been used in many applications. The examined tumour forms have varied and different detector systems and radiopharmaceuticals have also been used. The aim of this study was to evaluate and compare the ability of an NaI(Tl) scintillation detector to detect primary tumours and metastases in patients with different endocrine tumour types (e.g. carcinoid tumours, endocrine pancreatic tumours and thyroid tumours) and in patients with breast carcinoma or benign thyroid lesions, on the basis of their somatostatin receptor expression after i.v. injection of 111In-DTPA-D-Phe1-octreotide. Thirty patients were injected with 111In-DTPA-D-Phe1-octreotide intravenously. Scintigraphic images were taken 1 day after injection of the radiopharmaceutical, and surgery was performed 1-7 days post injection. An NaI(Tl) scintillation detector was used for intraoperative tumour detection. Tissue samples were collected during surgery for determination of 111In activity concentration and histopathological examination. The scintigraphic images were positive in 29 out of 30 patients. Intraoperative tumour detection was successful in 43 of 66 collected biopsies: 10 out of 11 for carcinoid tumours, 7 out of 10 for medullary thyroid carcinoma (MTC) and 14 out of 22 for breast cancer. On the basis of our findings we conclude that intraoperative tumour detection with 111In-DTPA-D-Phe1-octreotide using this NaI(Tl) detector can be successful especially for carcinoid tumours and endocrine pancreatic tumours, due to the relatively high activity concentrations in these tumour types, but is less successful in other forms of thyroid cancer, including MTC, and breast cancer. For successful intraoperative detection, the detector characteristics are also very important, and further improvement of the detector systems is required to increase the sensitivity and specificity. (orig.)

  14. Characterizing energy dependence and count rate performance of a dual scintillator fiber-optic detector for computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hoerner, Matthew R., E-mail: mrh5038@ufl.edu; Stepusin, Elliott J. [University of Florida, College of Medicine, P. O. Box 100374, Gainesville, Florida 32610 (United States); Hyer, Daniel E. [University of Iowa, 01615 Pomerantz Pavilion, Iowa City, Iowa 52242 (United States); Hintenlang, David E. [University of Florida, 1275 Center Drive, Biomedical Sciences Building JG-56 P. O. Box 116131, Gainesville, Florida 32611 (United States)

    2015-03-15

    Purpose: Kilovoltage (kV) x-rays pose a significant challenge for radiation dosimetry. In the kV energy range, even small differences in material composition can result in significant variations in the absorbed energy between soft tissue and the detector. In addition, the use of electronic systems in light detection has demonstrated measurement losses at high photon fluence rates incident to the detector. This study investigated the feasibility of using a novel dual scintillator detector and whether its response to changes in beam energy from scatter and hardening is readily quantified. The detector incorporates a tissue-equivalent plastic scintillator and a gadolinium oxysulfide scintillator, which has a higher sensitivity to scatter x-rays. Methods: The detector was constructed by coupling two scintillators: (1) small cylindrical plastic scintillator, 500 μm in diameter and 2 mm in length, and (2) 100 micron sheet of gadolinium oxysulfide 500 μm in diameter, each to a 2 m long optical fiber, which acts as a light guide to transmit scintillation photons from the sensitive element to a photomultiplier tube. Count rate linearity data were obtained from a wide range of exposure rates delivered from a radiological x-ray tube by adjusting the tube current. The data were fitted to a nonparalyzable dead time model to characterize the time response. The true counting rate was related to the reference free air dose air rate measured with a 0.6 cm{sup 3} Radcal{sup ®} thimble chamber as described in AAPM Report No. 111. Secondary electron and photon spectra were evaluated using Monte Carlo techniques to analyze ionization quenching and photon energy-absorption characteristics from free-in-air and in phantom measurements. The depth/energy dependence of the detector was characterized using a computed tomography dose index QA phantom consisting of nested adult head and body segments. The phantom provided up to 32 cm of acrylic with a compatible 0.6 cm{sup 3} calibrated

  15. Characterizing energy dependence and count rate performance of a dual scintillator fiber-optic detector for computed tomography

    International Nuclear Information System (INIS)

    Purpose: Kilovoltage (kV) x-rays pose a significant challenge for radiation dosimetry. In the kV energy range, even small differences in material composition can result in significant variations in the absorbed energy between soft tissue and the detector. In addition, the use of electronic systems in light detection has demonstrated measurement losses at high photon fluence rates incident to the detector. This study investigated the feasibility of using a novel dual scintillator detector and whether its response to changes in beam energy from scatter and hardening is readily quantified. The detector incorporates a tissue-equivalent plastic scintillator and a gadolinium oxysulfide scintillator, which has a higher sensitivity to scatter x-rays. Methods: The detector was constructed by coupling two scintillators: (1) small cylindrical plastic scintillator, 500 μm in diameter and 2 mm in length, and (2) 100 micron sheet of gadolinium oxysulfide 500 μm in diameter, each to a 2 m long optical fiber, which acts as a light guide to transmit scintillation photons from the sensitive element to a photomultiplier tube. Count rate linearity data were obtained from a wide range of exposure rates delivered from a radiological x-ray tube by adjusting the tube current. The data were fitted to a nonparalyzable dead time model to characterize the time response. The true counting rate was related to the reference free air dose air rate measured with a 0.6 cm3 Radcal® thimble chamber as described in AAPM Report No. 111. Secondary electron and photon spectra were evaluated using Monte Carlo techniques to analyze ionization quenching and photon energy-absorption characteristics from free-in-air and in phantom measurements. The depth/energy dependence of the detector was characterized using a computed tomography dose index QA phantom consisting of nested adult head and body segments. The phantom provided up to 32 cm of acrylic with a compatible 0.6 cm3 calibrated ionization chamber to

  16. Recent upgrades and performance of the CACTUS detector array

    Energy Technology Data Exchange (ETDEWEB)

    Schiller, A.; Bergholt, L.; Guttormsen, M. [and others

    1998-03-01

    The SCANDITRONIX MC-35 cyclotron laboratory, including the Oslo Cyclotron, has been in operation since 1980. The main auxiliary equipment consists of the multi-detector system CACTUS. During the last years, new, high efficiency Ge(HP) detectors were purchased and integrated in the CACTUS detector array. In this connection, the electronical setup was revised and altered. Several drawbacks of the old setup could be pointed out and eliminated. A test of the performance of all detector array elements was made with high accuracy. 27 refs.

  17. Recent upgrades and performance of the CACTUS detector array

    International Nuclear Information System (INIS)

    The SCANDITRONIX MC-35 cyclotron laboratory, including the Oslo Cyclotron, has been in operation since 1980. The main auxiliary equipment consists of the multi-detector system CACTUS. During the last years, new, high efficiency Ge(HP) detectors were purchased and integrated in the CACTUS detector array. In this connection, the electronical setup was revised and altered. Several drawbacks of the old setup could be pointed out and eliminated. A test of the performance of all detector array elements was made with high accuracy. 27 refs

  18. The Aachen muon detector prototype. Muon measurement using scintillator tiles with SiPM readout

    Energy Technology Data Exchange (ETDEWEB)

    Meissner, Rebecca; Bretz, Thomas; Hebbeker, Thomas; Lauscher, Markus; Middendorf, Lukas; Niggemann, Tim; Peters, Christine; Schumacher, Johannes [III. Physikalisches Institut A, RWTH Aachen University (Germany); Collaboration: Pierre Auger-Collaboration

    2015-07-01

    Muons being produced in air showers of ultra high energy cosmic rays carry important information on their characteristics such as the mass of the primary particle and the first hadronic interactions at the highest energies. In the context of the Pierre Auger Observatory this upgrade would enable an enhanced primary particle identification as well as the verification of shower simulation models. For this purpose, a simple and robust detector design with scintillator tiles and SiPM readout is being developed, the Aachen Muon Detector (AMD). AMD could be situated below the SD tanks which would provide shielding from the electromagnetic part of the shower. In total, 64 scintillating tiles form the sensitive area of the detector. Wavelength-shifting fibres are inserted into the tiles in sigma-shape to collect the light and are coupled to optical fibres to guide it onto the photosensitive SiPMs. By reading out each SiPM individually, an excellent and low-background performance is expected. Currently the AMD prototype is being built in Aachen and in parallel SiPM and electronics characteristics are being evaluated.

  19. A scintillating plastic fiber tracking detector for neutron and proton imaging and spectroscopy

    International Nuclear Information System (INIS)

    We report on a prototype detector system designed to perform imaging and spectroscopy on 20-250 MeV neutrons. The detection techniques employed can be applied to measurements in a variety of disciplines including solar and atmospheric physics, radiation therapy and nuclear materials monitoring. The detector measures the energy and direction of neutrons by detecting double neutron-proton scatters and recording images of the ionization tracks of the recoil protons in a densely packed bundle of scintillating plastic fibers stacked in orthogonal layers. The scintillation tracks are detected and imaged by photomultipliers and image intensifier/CCD camera optics. By tracking the recoil protons from individual neutrons, the kinematics of the scatter are determined. This directional information results in a high signal-to-noise measurement. The self-triggering and track imaging features of a prototype for tracking in two dimensions are demonstrated in calibrations with 14-65 MeV neutrons, 20-67.5 MeV protons, and with cosmic-ray muons. Preliminary results of phantom imaging measurements using a proton beam are also presented. We discuss several applications for this detector technique and outline future development work

  20. Characterization of a scintillating fibers read by MPPC detectors trigger prototype for the AMADEUS experiment

    CERN Document Server

    Scordo, A; Berucci, C; Curceanu, C; D'Uffizi, A; Piscicchia, K; Lener, M Poli; Vidal, A Romero; Sbardella, E; Doce, O Vazquez

    2013-01-01

    Multi-Pixel Photon Counters (MPPC) consist of hundreds of micro silicon Avalanche PhotoDiodes (APD) working in Geiger mode. The high gain and the low noise, typical of these devices, together with their good performance in magnetic field, make them ideal readout detectors for scintillating fibers as trigger detectors in particle and nuclear physics experiments like AMADEUS, where such detectors are planned to be used to trigger on charged kaon pairs. In order to investigate the detection efficiency of such a system, a prototype setup consisting of 32, 1 mm diameter scintillating fibers, arranged in two double layers of 16 fibers each, and read out by 64 MPPCs with an ad-hoc built readout electronics, was tested at the piM-1 line of the Paul Scherrer Institute (PSI) in Villigen, Switzerland. The detection efficiency and the trigger capability were measured on a beam containing protons, electrons, muons and pions with a momentum of 440 MeV/c. The measured average efficiency for protons for a double layer of sci...

  1. The customized groud test platforms for the plastic scintillator detector of DAMPE

    Science.gov (United States)

    Zhou, Yong; Sun, Zhiyu; Yu, Yuhong; Fang, Fang; Chen, Junling; Zhang, Yongjie

    2016-07-01

    The DArk Matter Particle Explorer (DAMPE) is a high-precision satellite-borne spectrometer aiming for dark matter search, understanding of the origin and propagation of cosmic rays and gamma-ray astronomy. The Plastic Scintillator Detector (PSD) is a key sub-detector of DAMPE, which provides the function of e/γ discrimination and charge measurement from proton to calcium. It consists of 82 plastic scintillator bars with the dimension of 884mm×28mm×10mm, each readout by two photomultiplier tubes (PMT) at both ends. To ensure the quality and achieve the best performance, various ground tests have been carried out during the construction phase of PSD both on the module and system scale. Customized test platforms are designed and constructed to facilitate these works which includes a test bench for batch PMT characterization and qualification with the capacity of 25 tubes, a test bench for batch scintillator bar characterization with the capacity of 24 bars, and an integrated platform which emulates the vacuum condition in space and provides accurate tracking of the incident cosmic ray particle for precise calibration of the PSD detector as a whole. A dedicated analysis software based on ROOT library has also been developed for PSD ground test, which can process both the engineering and science data, and combines decoding, analysis and data visualization into a single framework. These facilities constitute a complete test suite for PSD development and are applied successfully in the construction of both the Engineering Qualified Model and the Flight Model of PSD.

  2. A large-scale low-background liquid scintillation detector: the counting test facility at Gran Sasso

    Science.gov (United States)

    Alimonti, G.; Arpesella, C.; Bacchiocchi, G.; Balata, M.; Bellini, G.; Benziger, J.; Bonetti, S.; Brigatti, A.; Cadonati, L.; Calaprice, F. P.; Cavaletti, R.; Cecchet, G.; Chen, M.; Darnton, N.; Debari, A.; Deutsch, M.; Elisei, F.; von Feilitzsch, F.; Galbiati, C.; Garagiola, A.; Gatti, F.; Giammarchi, M. G.; Giugni, D.; Goldbrunner, T.; Golubchikov, A.; Goretti, A.; Grabar, S.; Hagner, T.; Hartmann, F.; von Hentig, R.; Heusser, G.; Ianni, A.; Jochum, J.; Johnson, M.; Laubenstein, M.; Loeser, F.; Lombardi, P.; Magni, S.; Malvezzi, S.; Manno, I.; Manuzio, G.; Masetti, F.; Mazzucato, U.; Meroni, E.; Neff, M.; Nisi, S.; Nostro, A.; Oberauer, L.; Perotti, A.; Preda, A.; Raghavan, P.; Raghavan, R. S.; Ranucci, G.; Resconi, E.; Ruscitti, P.; Scardaoni, R.; Schoenert, S.; Smirnov, O.; Tartaglia, R.; Testera, G.; Ullucci, P.; Vogelaar, R. B.; Vitale, S.; Zaimidoroga, O.

    1998-02-01

    A 4.8 m3 unsegmented liquid scintillation detector at the underground Laboratori Nazionali del Gran Sasso has shown the feasibility of multi-ton low-background detectors operating to energies as low as 250 keV. Detector construction and the handling of large volumes of liquid scintillator to minimize the background are described. The scintillator, 1.5 g PPO/L-pseudocumene, is held in a flexible nylon vessel shielded by 1000 t of purified water. The active detector volume is viewed by 100 photomultipliers, which measure time and charge for each event, from which energy, position and pulse shape are deduced. On-line purification of the scintillator by water extraction, vacuum distillation and nitrogen stripping removed radioactive impurities. Upper limits were established of thorium. The isotopic abundance of 14C/12C in the scintillator was shown to be approximately 10-18 by extending the energy window of the detector to 25-250 keV. The 14C abundance and uranium and thorium levels in the CTF are compatible with the Borexino Solar Neutrino Experiment.

  3. The Front End Electronics of the Scintillator Pad Detector of LHCb Calorimeter

    CERN Document Server

    Gascon, David; Bota, S; Comerma, A; Diéguez, A; Garrido, L; Gaspar, A; Graciani, R; Graciani, E; Herms, A; Llorens, M; Luengo, S; Picatoste, E; Riera, J; Rosselló, M; Ruiz, H; Tortella, S; Vilasís, X

    2007-01-01

    In this paper the Front End electronics of the Scintillator Pad Detector (SPD) is outlined. The SPD is a sub-system of the Calorimeter of the LHCb experiment designed to discriminate between charged and neutral particles for the first level trigger. The system design is presented, describing its different functionalities implemented through three different cards and several ASICs. These functionalities are signal processing and digitization, data transmission, interface with control and timing systems of the experiment, low voltage power supply distribution and monitoring. Special emphasis is placed on installation and commissioning subjects such as cabling, grounding, shielding and power distribution.

  4. Measurements of prompt fission gamma-rays and neutrons with lanthanide halide scintillation detectors

    CERN Document Server

    Oberstedt, A; Billnert, R; Borcea, R; Brys, T; Chaves, C; Gamboni, T; Geerts, W; Göök, A; Guerrero, C; Hambsch, F-J; Kis, Z; Martinez, T; Oberstedt, S; Szentmiklosi, L; Takács, K; Vivaldi, M

    2014-01-01

    Photons have been measured with lanthanide halide scintillation detectors in coincidence with fission fragments. Using the time-of-flight information, reactions from γ-rays and neutrons could easily be distinguished. In several experiments on $^{252}$Cf(sf), $^{235}$U(n$_{th}$,f) and $^{241}$Pu(n$_{th}$,f) prompt fission γ-ray spectra characteristics were determined with high precision and the results are presented here. Moreover, a measured prompt fission neutron spectrum for $^{235}$U(n$_{th}$,f) is shown in order to demonstrate a new detection technique.

  5. Alignment of the Near Detector scintillator modules using cosmic ray muons

    Energy Technology Data Exchange (ETDEWEB)

    Ospanov, Rustem; Lang, Karol; /Texas U.

    2008-05-01

    The authors describe the procedures and the results of the first alignment of the Near Detector. Using 15.5 million cosmic ray muon tracks, collected from October, 2004 through early january, 2005, they derive the effective transverse positions of the calorimeter scintillator modules. The residuals from straight line fits indicate that the current alignment has achieved better than 1 mm precision. They estimate the size of the remaining misalignment and using tracks recorded with a magnetic field test the effect of the magnetic field on the alignment.

  6. Time and position sensitive single photon detector for scintillator read-out

    OpenAIRE

    Schössler, Sven; Bromberger, Benjamin; Brandis, Michal; Schmidt, Lothar Ph. H.; Tittelmeier, Kai; Czasch, Achim; Dangendorf, Volker; Jagutzki, Ottmar

    2012-01-01

    We have developed a photon counting detector system for combined neutron and gamma radiography which can determine position, time and intensity of a secondary photon flash created by a high-energy particle or photon within a scintillator screen. The system is based on a micro-channel plate photomultiplier concept utilizing image charge coupling to a position- and time-sensitive read-out anode placed outside the vacuum tube in air, aided by a standard photomultiplier and very fast pulse-height...

  7. Extensive studies of MRS APDs for plastic scintillator muon veto detectors of cryogenic experiments

    Energy Technology Data Exchange (ETDEWEB)

    Falkenstein, R., E-mail: falkenst@pit.physik.uni-tuebingen.de [Kepler Center for Astro and Particle Physics, University of Tuebingen, Auf der Morgenstelle 14, 72076 Tuebingen (Germany); Bezrukov, L.B. [Institute for Nuclear Research of RAS, Moscow (Russian Federation); Freund, K. [Kepler Center for Astro and Particle Physics, University of Tuebingen, Auf der Morgenstelle 14, 72076 Tuebingen (Germany); Golovin, A.V.; Golovin, V.M. [Centre for Perspective Technology and Apparatus, Moscow (Russian Federation); Grabmayr, P.; Jochum, J. [Kepler Center for Astro and Particle Physics, University of Tuebingen, Auf der Morgenstelle 14, 72076 Tuebingen (Germany); Lubsandorzhiev, B.K. [Kepler Center for Astro and Particle Physics, University of Tuebingen, Auf der Morgenstelle 14, 72076 Tuebingen (Germany); Institute for Nuclear Research of RAS, Moscow (Russian Federation); Lubsandorzhiev, N.B.; Poleshuk, R.V. [Institute for Nuclear Research of RAS, Moscow (Russian Federation); Polyansky, I.N. [Centre for Perspective Technology and Apparatus, Moscow (Russian Federation); Ritter, F.; Sailer, C. [Kepler Center for Astro and Particle Physics, University of Tuebingen, Auf der Morgenstelle 14, 72076 Tuebingen (Germany); Shaibonov, B.A.M. [Institute for Nuclear Research of RAS, Moscow (Russian Federation)

    2012-12-11

    Low background experiments need active muon veto detectors to shield them from cosmic muons. Plastic scintillator panels with WLS fiber and multi-pixel Geiger-mode avalanche photodiodes readout are widely used in such experiments due to their compactness and robustness. In this paper, results from the study of the basic MRS APD parameters, such as breakdown voltages, quenching resistors, internal gain and dark count rates are presented, as well as temperature dependencies of some of these parameters. In a small fraction of the MRS APDs, some strange dips in the I-V curves just preceding the breakdown voltage point have been observed.

  8. A rope-net support system for the liquid scintillator detector for the SNO+ experiment

    Science.gov (United States)

    Bialek, A.; Chen, M.; Cleveland, B.; Gorel, P.; Hallin, A.; Harvey, P. J.; Heise, J.; Kraus, C.; Krauss, C. B.; Lawson, I.; Ng, C. J.; Pinkney, B.; Rogowsky, D. M.; Sibley, L.; Soluk, R.; Soukup, J.; Vázquez-Jáuregui, E.

    2016-08-01

    The detector for the SNO+ experiment consists of 780 000 kg of liquid scintillator contained in an acrylic vessel that is surrounded by water. A mechanical system has been installed to counteract the 1.25 MN of buoyant force on the acrylic and prevent the vessel from moving. The system is a rope net, designed using a Finite Element Analysis to calculate the amount of stress on the acrylic induced by the ropes, hydrostatic pressures and gravity. A dedicated test was performed to measure strains in the acrylic arising from the complex geometry of the knots in the rope system. The ratio between measured and FEA calculated strains was 1.3.

  9. A large acceptance scintillator detector with wavelength shifting fibre readout for search of η-nucleus bound states

    Science.gov (United States)

    Betigeri, M. G.; Biswas, P. K.; Budzanowski, A.; Chatterjee, A.; Jahn, R.; Guha, S.; Hawranek, P.; Jain, B. K.; Jawale, S. B.; Jha, V.; Kilian, K.; Kliczewski, S.; Kirillov, Da.; Kirillov, Di.; Kolev, D.; Kravcikova, M.; Kutsarova, T.; Lesiak, M.; Lieb, J.; Machner, H.; Magiera, A.; Maier, R.; Martinska, G.; Nedev, S.; Piskunov, N.; Prasuhn, D.; Protić, D.; Ritman, J.; von Rossen, P.; Roy, B. J.; Shukla, P.; Sitnik, I.; Siudak, R.; Tsenov, R.; Ulicny, M.; Urban, J.; Vankova, G.; GEM Collaboration

    2007-07-01

    A large acceptance scintillator detector with wavelength shifting optical fibre readout has been designed and built to detect the decay particles of η-nucleus bound system (the so-called η-mesic nuclei), namely, protons and pions. The detector, named as ENSTAR detector, consists of 122 pieces of plastic scintillator of various shapes and sizes, which are arranged in a cylindrical geometry to provide particle identification, energy loss and coarse position information for these particles. A solid angle coverage of ˜95% of total 4 π is obtained in the present design of the detector. Monte Carlo phase space calculations performed to simulate the formation and decay of η-mesic nuclei suggest that its decay particles, the protons and pions are emitted with an opening angle of 150±20∘, and with energies in the range of 25-300 and 225-450 MeV, respectively. The detailed GEANT simulations show that ˜80 % of the decay particles (protons and pions) can be detected within ENSTAR. Several test measurements using alpha source, cosmic-ray muons, etc. have been carried out to study the response of ENSTAR scintillator pieces. The in-beam tests of fully assembled detector with proton beam of momentum 870 MeV/c from the Cooler synchrotron COSY have been performed. The test results show that the scintillator fibre design chosen for the detector has performed satisfactorily well. The present article describes the detector design, simulation studies, construction details and test results.

  10. Mercury Cadmium Telluride Photoconductive Long Wave Infrared Linear Array Detectors

    Directory of Open Access Journals (Sweden)

    Risal Singh

    2003-07-01

    Full Text Available Mercury cadmium telluride (Hg1-x, CdxTe (MCT photoconductive long wave infrared linear arrays are still in demand due to several advantages. The linear array technology is well established, easier, economical and is quite relevant to thermal imaging even today. The scan thermal imaging systems based on this technology offer wider field of view coverage and capacity for higher resolution in the scan direction relative to staring systems that use expensive and yet to mature focal plane array detector technology. A critical review on photoconductive n-Hg1-x CdxTe linear array detector technology for the long wave infrared range has been presented. The emphasis lies on detector design and processing technology. The critical issues of diffusion and drift effects, Hi-Lo and heterostructure blocking contacts, surface passivation, and other related aspects have been considered from the detector design angle. The device processing technology aspects are of vital importance

  11. Developments in large gamma-ray detector arrays

    CERN Document Server

    Lee, I Y; Vetter, K

    2003-01-01

    Gamma-ray spectroscopy was revolutionized with the introduction of high energy-resolution semiconductor germanium (Ge) detectors in the early 1960s. This led to the large increase in sensitivity realized by today's arrays of Compton-suppressed Ge detectors. A still larger increase in sensitivity is expected by implementing the new concept of tracking. A tracking array consists of highly segmented Ge detectors (that can cover the full 4 pi solid-angle) in which gamma rays will be identified by measuring and tracking every gamma ray interaction. This article reviews the physics motivation for such detectors and the development of the new technologies involved. The concept of tracking is explained using the example of a proposed array called gamma-ray energy tracking array (GRETA).

  12. Neutron detector based on Particles of 6Li glass scintillator dispersed in organic lightguide matrix

    International Nuclear Information System (INIS)

    Most 3He replacement neutron detector technologies today have overlapping neutron–gamma pulse-height distributions, which limits their usefulness and performance. Different techniques are used to mitigate this shortcoming, including Pulse Shape Discrimination (PSD) or threshold settings that suppress all gammas as well as much of the neutrons. As a result, count rates are limited and dead times are high when PSD is used, and the detection efficiency for neutron events is reduced due to the high threshold. This is a problem in most applications where the neutron–gamma separation of 3He detectors had been essential. This challenge is especially severe for neutron coincidence and multiplicity measurements that have numerous conflicting requirements such as high detection efficiency, short die-away time, short dead time, and high stability. 6Li-glass scintillators have excellent light output and a single peak distribution, but they are difficult to implement because of their gamma sensitivity. The idea of reducing the gamma sensitivity of 6Li-glass scintillators by embedding small glass particles in an organic light-guide medium was first presented by L.M. Bollinger in the early 60s but, to the best of our knowledge, has never been reduced to practice. We present a proof of principle detector design and experimental data that develop this concept to a large-area neutron detector. This is achieved by using a multi-component optical medium (6Li glass particles attached to a glass supporting structure and a mineral oil light guide) which matches the indices of refraction and minimizes the absorption of the 395 nm scintillator light. The detector design comprises a 10 in. long tube with dual end readout with about 3% volume density of 6Li glass particles installed. The presented experimental data with various neutron and gamma sources show the desired wide gap between the neutron and gamma pulse height distributions, resulting in a true plateau in the counting

  13. Data acquisition for experiments with multi-detector arrays

    Indian Academy of Sciences (India)

    A Chatterjee; Sushil Kamerkar; A K Jethra; S Padmini; M P Diwakar; S S Pande; M D Ghodgaonkar

    2001-07-01

    Experiments with multi-detector arrays have special requirements and place higher demands on computer data acquisition systems. In this contribution we discuss data acquisition systems with special emphasis on multi-detector arrays and in particular we describe a new data acquisition system, AMPS which we have developed recently which is in regular use in experiments at the Pelletron Laboratory, Mumbai. This includes the in-house development of a dedicated crate controller, PC interface card and software.

  14. Monte Carlo and analytical models of neutron detection with organic scintillation detectors

    International Nuclear Information System (INIS)

    This paper presents a new technique for the analysis of neutron pulse height distributions generated in an organic scintillation detector. The methodology presented can be applied to techniques such as neutron spectrum unfolding, which have a variety of applications, including nuclear nonproliferation and homeland security. The technique is based on two independent approaches: (i) the use of the MCNP-PoliMi code to simulate neutron detection on an event-by-event basis with the Monte Carlo method and (ii) an analytical approach for neutron slowing down and detection processes. We show that the total neutron pulse height response measured by the organic scintillators is given by the sum of a large number of different neutron histories, each composed of a certain number of neutron scatterings on hydrogen and/or carbon. The relative contributions of each of these histories are described for a cylindrical liquid scintillator BC-501A. Simulations and measurements of neutron pulse height distributions are essential for neutron spectrum unfolding procedures

  15. Modular design for narrow scintillating cells with MRS photodiodes in strong magnetic field for ILC detector

    Science.gov (United States)

    Beznosko, D.; Blazey, G.; Dyshkant, A.; Rykalin, V.; Schellpffer, J.; Zutshi, V.

    2006-08-01

    The experimental results for the narrow scintillating elements with effective area about 20 cm 2 are reported. The elements were formed from the single piece of scintillator and were read out via wavelength shifting (WLS) fibers with the Metal/Resistor/Semiconductor (MRS) photodiodes on both ends of each fiber. The count rates were obtained using radioactive source 90Sr, with threshold at about three photoelectrons in each channel and quad coincidences (double coincidences between sensors on each fiber and double coincidences between two neighboring fibers). The formation of the cells from the piece of scintillator by using grooves is discussed, and their performances were tested using the radioactive source by measuring the photomutiplier current using the same WLS fiber. Because effective cell area can be readily enlarged or reduced, this module may be used as an active element for calorimeter or muon system for the design of the future electron-positron linear collider detector. Experimental verification of the performance of the MRS photodiode in a strong magnetic field of 9 T, and the impact a magnet quench at 9.5 T are reported. The measurement method used is described. The results confirm the expectations that the MRS photodiode is insensitive to a strong magnetic field and therefore applicable to calorimetry in the presence of magnetic field. The overall result is of high importance for large multi-channel systems.

  16. The surface detector array of the Telescope Array experiment to explore the highest energy cosmic rays

    CERN Document Server

    Abu-Zayyad, T; Allen, M; Anderson, R; Azuma, R; Barcikowski, E; Belz, J W; Bergman, D R; Blake, S A; Cady, R; Cheon, B G; Chiba, J; Chikawa, M; Cho, E J; Cho, W R; Fujii, H; Fujii, T; Fukuda, T; Fukushima, M; Gorbunov, D; Hanlon, W; Hayashi, K; Hayashi, Y; Hayashida, N; Hibino, K; Hiyama, K; Honda, K; Iguchi, T; Ikeda, D; Ikuta, K; Inoue, N; Ishii, T; Ishimori, R; Ivanov, D; Iwamoto, S; Jui, C C H; Kadota, K; Kakimoto, F; Kalashev, O; Kanbe, T; Kasahara, K; Kawai, H; Kawakami, S; Kawana, S; Kido, E; Kim, H B; Kim, H K; Kim, J H; Kim, J H; Kitamoto, K; Kobayashi, K; Kobayashi, Y; Kondo, Y; Kuramoto, K; Kuzmin, V; Kwon, Y J; Lim, S I; Machida, S; Martens, K; Martineau, J; Matsuda, T; Matsuura, T; Matsuyama, T; Matthews, J N; Myers, I; Minamino, M; Miyata, K; Miyauchi, H; Murano, Y; Nakamura, T; Nam, S W; Nonaka, T; Ogio, S; Ohnishi, M; Ohoka, H; Oki, K; Oku, D; Okuda, T; Oshima, A; Ozawa, S; Park, I H; Pshirkov, M S; Rodriguez, D; Roh, S Y; Rubtsov, G; Ryu, D; Sagawa, H; Sakurai, N; Sampson, A L; Scott, L M; Shah, P D; Shibata, F; Shibata, T; Shimodaira, H; Shin, B K; Shin, J I; Shirahama, T; Smith, J D; Sokolsky, P; Sonley, T J; Springer, R W; Stokes, B T; Stratton, S R; Stroman, T A; Suzuki, S; Takahashi, Y; Takeda, M; Taketa, A; Takita, M; Tameda, Y; Tanaka, H; Tanaka, K; Tanaka, M; Thomas, S B; Thomson, G B; Tinyakov, P; Tkachev, I; Tokuno, H; Tomida, T; Troitsky, S; Tsunesada, Y; Tsutsumi, K; Tsuyuguchi, Y; Uchihori, Y; Udo, S; Ukai, H; Vasiloff, G; Wada, Y; Wong, T; Wood, M; Yamakawa, Y; Yamaoka, H; Yamazaki, K; Yang, J; Yoshida, S; Yoshii, H; Zollinger, R; Zundel, Z

    2012-01-01

    The Telescope Array (TA) experiment, located in the western desert of Utah,USA, is designed for observation of extensive air showers from extremely high energy cosmic rays. The experiment has a surface detector array surrounded by three fluorescence detectors to enable simultaneous detection of shower particles at ground level and fluorescence photons along the shower track. The TA surface detectors and fluorescence detectors started full hybrid observation in March, 2008. In this article we describe the design and technical features of the TA surface detector.

  17. Study of a detector system for high-energy astrophysical objects using a combination of plastic scintillator and MPPC

    Science.gov (United States)

    Nakaoka, Tatsuya; Mizuno, Tsunefumi; Takahashi, Hiromitsu; Fukazawa, Yasushi

    2016-09-01

    We have investigated a hard X-ray detector system using a combination of a plastic scintillator and multi-pixel photon counters (MPPC). Photomultiplier tubes (PMTs) have typically been adopted to read scintillators because of their high gain and large photoelectric surface, and studies on PMT and scintillator systems are well advanced. However, PMTs have limitations; for example, they are relatively large in size, require high voltage to operate, and cannot be used in strong magnetic fields. On the other hand, MPPCs do not have such limitations and instead possess high quantum efficiency and a large compact size. Therefore, we have studied a detector system that combines an MPPC with a plastic scintillator. The system is primarily intended to be used for polarization measurements of high-energy astrophysical objects. We achieved an energy threshold of as low as ~5 keV while operating the detector at low temperature (-10 °C), reading the signal with short integration time (50 ns), and using a low-noise MPPC. We also confirmed that the light yield of our MPPC+plastic scintillator system is comparable to that obtained using a conventional PMT to read the scintillator signal. Herein, we report test results and future prospects.

  18. Influence of scintillator's thickness on imaging quality of lens-coupled hard X-ray imaging detector

    International Nuclear Information System (INIS)

    Background: Scintillator is an important component of synchrotron X-ray imaging detector's, which converts the incident X-rays into visible light to be imaged by visible light imaging detectors. The thickness of scintillators has a great impact on the spatial resolution and contrast of the images. When the thickness of the scintillator is matched with detector lens (NA), image quality of experimental results will be improved obviously. But in fact, users doing X-ray imaging experiments at Shanghai Synchrotron Radiation Facility (SSRF) don't take into account this factor and it is difficult to obtain the best results with high image quality. Purpose: Matching thickness of scintillators with NA of objective can help us get good experimental results with high-quality images. Methods: We obtain the optimal thickness of scintillator for every objective lens by the way of mathematical computations of resolution theoretical curves and analysis of image contrast of experimental results. Results: Both of the results are nearly in accordance with each other. Conclusion: Users of SSRF will get better results of X-ray imaging experiment than before when they chose the optimal thickness of scintillator matched with the objective lens. (authors)

  19. A systematic characterization of the low-energy photon response of plastic scintillation detectors

    Science.gov (United States)

    Boivin, Jonathan; Beddar, Sam; Bonde, Chris; Schmidt, Daniel; Culberson, Wesley; Guillemette, Maxime; Beaulieu, Luc

    2016-08-01

    To characterize the low energy behavior of scintillating materials used in plastic scintillation detectors (PSDs), 3 PSDs were developed using polystyrene-based scintillating materials emitting in different wavelengths. These detectors were exposed to National Institute of Standards and Technology (NIST)-matched low-energy beams ranging from 20 kVp to 250 kVp, and to 137Cs and 60Co beams. The dose in polystyrene was compared to the dose in air measured by NIST-calibrated ionization chambers at the same location. Analysis of every beam quality spectrum was used to extract the beam parameters and the effective mass energy-absorption coefficient. Monte Carlo simulations were also performed to calculate the energy absorbed in the scintillators’ volume. The scintillators’ expected response was then compared to the experimental measurements and an energy-dependent correction factor was identified to account for low-energy quenching in the scintillators. The empirical Birks model was then compared to these values to verify its validity for low-energy electrons. The clear optical fiber response was below 0.2% of the scintillator’s light for x-ray beams, indicating that a negligible amount of fluorescence contamination was produced. However, for higher-energy beams (137Cs and 60Co), the scintillators’ response was corrected for the Cerenkov stem effect. The scintillators’ response increased by a factor of approximately 4 from a 20 kVp to a 60Co beam. The decrease in sensitivity from ionization quenching reached a local minimum of about 11%+/- 1% between 40 keV and 60 keV x-ray beam mean energy, but dropped by 20% for very low-energy (13 keV) beams. The Birks model may be used to fit the experimental data, but it must take into account the energy dependence of the kB quenching parameter. A detailed comprehension of intrinsic scintillator response is essential for proper calibration of PSD dosimeters for radiology.

  20. A compact gamma camera with scintillation array and parallel-hole collimator

    Institute of Scientific and Technical Information of China (English)

    ZHU Jie; MA Hongguang; MA Wenyan; ZENG Hui; WANG Zhaomin; XU Zizhong

    2008-01-01

    A new compact gamma camera for small object imaging has been developed. It consists of a pixelized Nal(T1) scintillator array coupled to a position sensitive photomultiplier tube (Hamamatsu R2486) with a parallel-hole lead collimator. The compact camera has better spatial resolution than Anger camera. The average value of intrinsic spatial resolutions is 2.3 mm (FWHM). The overall spatial resolution (FWHM) is 3, 5 and 6 mm at 0, 2.5 and 3 mm SCD (source-to-collimator distance), respectively. The phantom studies with the compact camera have demonstrated that parallel-hole collimator gamma camera is a practical technique for nuclear medicine application.

  1. Development of a new neutron monitor using a boron-loaded organic liquid scintillation detector

    CERN Document Server

    Rasolonjatovo, A H D; Kim, E; Nakamura, T; Nunomiya, T; Endo, A; Yamaguchi, Y; Yoshizawa, M

    2002-01-01

    A new type of neutron dose monitor was developed by using a 12.7 cm diameterx12.7 cm long boron-loaded organic liquid scintillation detector BC523A. This detector aims to have a response in the wide energy range of thermal energy to 100 MeV by using the H and C reactions to the fast neutrons of organic liquid and the sup 1 sup 0 B(n, alpha) reaction to thermalized neutrons in the liquid. The response functions of this detector were determined by the Monte Carlo simulation in the energy region from thermal energy to 100 MeV. Using these response functions, the spectrum-weighted dose function, G-function, to get the neutron dose from the light output spectrum of the detector was also determined by the unfolding technique. The calculated G-function was applied to determine the neutron dose in real neutron fields having energies ranging from thermal energy to several tens of MeV, where the light output spectra were measured with the BC523A detector. The thus-obtained ambient doses and effective doses show rather ...

  2. Digital discrimination of neutrons and gamma-rays in organic scintillation detectors using moment analysis.

    Science.gov (United States)

    Xie, Xufei; Zhang, Xing; Yuan, Xi; Chen, Jinxiang; Li, Xiangqing; Zhang, Guohui; Fan, Tieshuan; Yuan, Guoliang; Yang, Jinwei; Yang, Qingwei

    2012-09-01

    Digital discrimination of neutron and gamma-ray events in an organic scintillator has been investigated by moment analysis. Signals induced by an americium-beryllium (Am/Be) isotropic neutron source in a stilbene crystal detector have been sampled with a flash analogue-to-digital converter (ADC) of 1 GSamples/s sampling rate and 10-bit vertical resolution. Neutrons and gamma-rays have been successfully discriminated with a threshold corresponding to gamma-ray energy about 217 keV. Moment analysis has also been verified against the results assessed by a time-of-flight (TOF) measurement. It is shown that the classification of neutrons and gamma-rays afforded by moment analysis is consistent with that achieved by digital TOF measurement. This method has been applied to analyze the data acquired from the stilbene crystal detector in mixed radiation field of the HL-2A tokamak deuterium plasma discharges and the results are described. PMID:23020376

  3. 'Speed of light' measurement using BaF2 scintillation detectors

    International Nuclear Information System (INIS)

    State-of-the-art timing technique is used to determine the 'speed of light' in an upper level undergraduate laboratory experiment. In this experiment we use the correlated 511 keV photons from positron annihilation obtained from a 100 μ Ci Na-22 source. The photons were detected by two BaF2 scintillation detectors and, after careful time calibration of the entire counting system, the prompt coincidence peaks were each recorded as a function of the position of one of the detectors. As a result, the 'speed of light' was determined to be 3.002(16)*1010 cm s-1, which is very close to the defined value of 2.99792*1010 cm s-1. This experiment demonstrates the utilization of various nuclear instrumentation and timing equipment. (author)

  4. Unfolding the fast neutron spectra of a BC501A liquid scintillation detector using GRAVEL method

    CERN Document Server

    Chen, Yonghao; Lei, Jiarong; An, Li; Zhang, Xiaodong; Shao, Jianxiong; Zheng, Pu; Wang, Xinhua

    2013-01-01

    Accurate knowledge of the neutron energy spectra is useful in basic research and applications. The overall procedure of measuring and unfolding the fast neutron energy spectra with BC501A liquid scintillation detector is described. The recoil proton spectrum of Am-Be neutrons was obtained experimentally. With the NRESP7 code, the response matrix of detector was simulated. Combining the recoil proton spectrum and response matrix, the unfolding of neutron spectra was performed by GRAVEL iterative algorithm. A MatLab program based on the GRAVEL method was developed. The continuous neutron spectrum of Am-Be source and monoenergetic neutron spectrum of D-T source have been unfolded successfully and are in good agreement with their standard reference spectra. The unfolded Am-Be spectrum are more accurate than the spectra unfolded by artificial neural networks in recent years.

  5. Unfolding the fast neutron spectra of a BC501A liquid scintillation detector using GRAVEL method

    Science.gov (United States)

    Chen, YongHao; Chen, XiMeng; Lei, JiaRong; An, Li; Zhang, XiaoDong; Shao, JianXiong; Zheng, Pu; Wang, XinHua

    2014-10-01

    Accurate knowledge of the neutron energy spectra is useful in basic research and applications. The overall procedure of measuring and unfolding the fast neutron energy spectra with BC501A liquid scintillation detector is described. The recoil proton spectrum of 241Am-Be neutrons was obtained experimentally. With the NRESP7 code, the response matrix of detector was simulated. Combining the recoil proton spectrum and response matrix, the unfolding of neutron spectra was performed by GRAVEL iterative algorithm. A MatLab program based on the GRAVEL method was developed. The continuous neutron spectrum of 241Am-Be source and monoenergetic neutron spectrum of D-T source have been unfolded successfully and are in good agreement with their standard reference spectra. The unfolded 241Am-Be spectrum are more accurate than the spectra unfolded by artificial neural networks in recent years.

  6. Large arrays of discrete ionizing radiation detectors multiplexed using fluorescent optical converters

    International Nuclear Information System (INIS)

    This invention provides a radiation imaging system employing arrays of scintillators. An object of the invention is to produce a detector with high spatial resolution, high gamma-photon absorption efficiency, excellent source and detector scatter rejection, and utilizing low-cost solid state opto-electronic devices. In one embodiment, it provides a radiation detection and conversion apparatus having an array of optically isolated radiation sensitive elements that emit optical radiation upon absorption of ionizing radiation. An array of channels, comprising a material that absorbs and traps the radiation emitted and transports it or radiation that has been shifted to longer wavelengths, is placed near the radiation-sensitive elements. Electro-optical detectors that convert the transported radiation into electrical signals are coupled to the channels. The activation of one of the electro-optical devices by radiation from one of the channels indicates that at least one of the radiation-sensitive elements near that channel has absorbed a quantity of radiation

  7. Positron discrimination in large-volume liquid scintillator detectors using 3D topological reconstruction

    International Nuclear Information System (INIS)

    Over the last 20 years, large-volume liquid scintillator detectors have been very successful in measuring neutrinos with energies of a few MeV. One main feature responsible for this is the coincidence between a prompt positron signal and the delayed neutron signal coming from an inverse beta decay. This is used to identify electron anti-neutrinos with high efficiency. However, background mimicking this coincidence e.g. from cosmogenics can still be a limiting factor for this kind of experiments. Therefore, the possibility to individually identify positrons is highly desirable. In addition, this capability would enable the discrimination of beta+ decays and thus increase the potential to discover CNO-neutrinos from the Sun where the beta+ decay of C-11 is a major background source. In this talk, we present a new reconstruction method delivering 3D topological pictures of the energy deposition in large-volume liquid scintillator detectors with a resolution of better than 20 cm. This method was originally developed for high-energy particles of a few GeV. However, it turned out that even at low energies it can reveal some topological information containing hints on the presence of photons accompanying a positron annihilation.

  8. Towards large scale HTS Josephson detector arrays for THz imaging

    Science.gov (United States)

    Du, J.; Hellicar, A. D.; Leslie, K. E.; Nikolic, N.; Hanham, S. M.; Macfarlane, J. C.; Foley, C. P.

    2013-11-01

    We present the design and implementation of a high-temperature superconducting (HTS) Josephson junction detector array for terahertz (THz) imaging. The array device is made of ten YBa2Cu3Ox-7 (YBCO) step-edge junctions coupled to gold thin-film ring-slot antennas on a MgO substrate. The design and characterization of the detector array in response to a 0.6 THz signal are presented. The development of multi-channel biasing and read-out electronics and the system integration with a commercial cryocooler are also described.

  9. Towards large scale HTS Josephson detector arrays for THz imaging

    International Nuclear Information System (INIS)

    We present the design and implementation of a high-temperature superconducting (HTS) Josephson junction detector array for terahertz (THz) imaging. The array device is made of ten YBa2Cu3Ox−7 (YBCO) step-edge junctions coupled to gold thin-film ring-slot antennas on a MgO substrate. The design and characterization of the detector array in response to a 0.6 THz signal are presented. The development of multi-channel biasing and read-out electronics and the system integration with a commercial cryocooler are also described. (paper)

  10. New air fluorescence detectors employed in the Telescope Array experiment

    CERN Document Server

    Tokuno, H; Takeda, M; Kadota, K; Ikeda, D; Chikawa, M; Fujii, T; Fukushima, M; Honda, K; Inoue, N; Kakimoto, F; Kawana, S; Kido, E; Matthews, J N; Nonaka, T; Ogio, S; Okuda, T; Ozawa, S; Sagawa, H; Sakurai, N; Shibata, T; Taketa, A; Thomas, S B; Tomida, T; Tsunesada, Y; Udo, S; Abu-zayyad, T; Aida, R; Allen, M; Anderson, R; Azuma, R; Barcikowski, E; Belz, J W; Bergman, D R; Blake, S A; Cady, R; Cheon, B G; Chiba, J; Cho, E J; Cho, W R; Fujii, H; Fukuda, T; Gorbunov, D; Hanlon, W; Hayashi, K; Hayashi, Y; Hayashida, N; Hibino, K; Hiyama, K; Iguchi, T; Ikuta, K; Ishii, T; Ishimori, R; Ivanov, D; Iwamoto, S; Jui, C C H; Kalashev, O; Kanbe, T; Kasahara, K; Kawai, H; Kawakami, S; Kim, H B; Kim, H K; Kim, J H; Kim, J H; Kitamoto, K; Kobayashi, K; Kobayashi, Y; Kondo, Y; Kuramoto, K; Kuzmin, V; Kwon, Y J; Lim, S I; Machida, S; Martens, K; Martineau, J; Matsuda, T; Matsuura, T; Matsuyama, T; Myers, I; Minamino, M; Miyata, K; Miyauchi, H; Murano, Y; Nakamura, T; Nam, S W; Ohnishi, M; Ohoka, H; Oki, K; Oku, D; Oshima, A; Park, I H; Pshirkov, M S; Rodriguez, D; Roh, S Y; Rubtsov, G; Ryu, D; Sampson, A L; Scott, L M; Shah, P D; Shibata, F; Shimodaira, H; Shin, B K; Shin, J I; Shirahama, T; Smith, J D; Sokolsky, P; Sonley, T J; Springer, R W; Stokes, B T; Stratton, S R; Stroman, T; Suzuki, S; Takahashi, Y; Takita, M; Tanaka, H; Tanaka, K; Tanaka, M; Thomson, G B; Tinyakov, P; Tkachev, I; Troitsky, S; Tsutsumi, K; Tsuyuguchi, Y; Uchihori, Y; Ukai, H; Vasiloff, G; Wada, Y; Wong, T; Wood, M; Yamakawa, Y; Yamaoka, H; Yamazaki, K; Yang, J; Yoshida, S; Yoshii, H; Zollinger, R; Zundel, Z

    2012-01-01

    Since 2007, the Telescope Array (TA) experiment, based in Utah, USA, has been observing ultra high energy cosmic rays to understand their origins. The experiment involves a surface detector (SD) array and three fluorescence detector (FD) stations. FD stations, installed surrounding the SD array, measure the air fluorescence light emitted from extensive air showers (EASs) for precise determination of their energies and species. The detectors employed at one of the three FD stations were relocated from the High Resolution Fly's Eye experiment. At the other two stations, newly designed detectors were constructed for the TA experiment. An FD consists of a primary mirror and a camera equipped with photomultiplier tubes. To obtain the EAS parameters with high accuracies, understanding the FD optical characteristics is important. In this paper, we report the characteristics and installation of new FDs and the performances of the FD components. The results of the monitored mirror reflectance during the observation ti...

  11. Numerical study of point spread function of a fast neutron radiography system based on scintillating-fiber array

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ For a scintillating-fiber array fast-neutron radiography system, a point-spread- function computing model was introduced, and the simulation code was developed. The results of calculation show that fast-neutron radiographs vary with the size of fast neutron sources, the size of fiber cross-section and the imaging geometry. The results suggest that the following qualifications are helpful for a good point spread function: The cross-section of scintillating fibers not greater than 200μm×200μm, the size of neutron source as small as a few millimeters, the distance between the source and the scintillating fiber array greater than 1 m, and inspected samples placed as close as possible to the array. The results give suggestions not only to experiment considerations but also to the estimation of spatial resolution for a specific system.

  12. Numerical study of point spread function of a fast neutron radiography system based on scintillating-fiber array

    Institute of Scientific and Technical Information of China (English)

    ZHANG; FaQiang

    2007-01-01

    For a scintillating-fiber array fast-neutron radiography system, a point-spread- function computing model was introduced, and the simulation code was developed. The results of calculation show that fast-neutron radiographs vary with the size of fast neutron sources, the size of fiber cross-section and the imaging geometry. The results suggest that the following qualifications are helpful for a good point spread function: The cross-section of scintillating fibers not greater than 200μm×200μm, the size of neutron source as small as a few millimeters, the distance between the source and the scintillating fiber array greater than 1 m, and inspected samples placed as close as possible to the array. The results give suggestions not only to experiment considerations but also to the estimation of spatial resolution for a specific system.……

  13. Scintillation dosimeter arrays using air core light guides: simulation and experiment

    Energy Technology Data Exchange (ETDEWEB)

    Naseri, Pourandokht; Suchowerska, Natalka; McKenzie, David R, E-mail: p.naseri@physics.usyd.edu.a [School of Physics, University of Sydney, Applied Physics, Sydney, NSW, 2006 (Australia)

    2010-06-21

    The performance of a scintillation dosimeter that uses a silvered air core light guide is examined by Monte Carlo (MC) simulations and by experiment to determine its suitability for array dosimetry in external beam radiotherapy. The air core light guide avoids the generation of the Cerenkov background that is produced in a conventional optical fibre. MC simulations using a 6 MV photon beam showed that silver thicknesses of less than 1 {mu}m compensated for the effects of the other material components, to give the dosimeter water equivalence within 0.5%. A second dosimeter located adjacent to the primary dosimeter in any direction affected the dose measurement by less than 1.5%, when the centre-to-centre spacing was 1.3 mm or greater. When the dosimeter array is located perpendicular to the beam central axis, with a spacing of 2.5 mm, the calculated deviation from the dose deposited in water was less than 2%. When the dosimeter array is located parallel to the beam central axis with a spacing of 10 mm, the calculated dose readings deviated from water by less than 2.5%. The simulation results were confirmed with experiment for two neighbouring dosimeters and a small densely packed array. No proximity effects were measured within the experimental error of {+-}1.5%. These results confirm the dosimetric accuracy of the air core dosimeter design without the need for correction factors. The dosimeter has excellent potential for use in arrays.

  14. Characterization of scintillator materials for fast-ion loss detectors in nuclear fusion reactors

    Science.gov (United States)

    Jiménez-Ramos, M. C.; García López, J.; García-Muñoz, M.; Rodríguez-Ramos, M.; Carmona Gázquez, M.; Zurro, B.

    2014-08-01

    In fusion plasma reactors, fast ion generated by heating systems and fusion born particles must be well confined. The presence of magnetohydrodynamic (MHD) instabilities can lead to a significant loss of these ions, which may reduce drastically the heating efficiency and may cause damage to plasma facing components in the vacuum vessel. In order to understand the physics underlying the fast ion loss mechanism, scintillator based detectors have been installed in several fusion devices. In this work we present the absolute photon yield and its degradation with ion fluence in terms of the number of photons emitted per incident ion of several scintillators thin coatings: SrGa2S4:Eu2+ (TG-Green), Y3Al5O12:Ce3+ (P46) and Y2O3:Eu3+ (P56) when irradiated with light ions of different masses (deuterium ions, protons and α-particles) at energies between approximately 575 keV and 3 MeV. The photon yield will be discussed in terms of the energy deposited by the particles into the scintillator. For that, the actual composition and thickness of the thin layers were determined by Rutherford Backscattering Spectrometry (RBS). A collimator with 1 mm of diameter, which defines the beam size for the experiments, placed at the entrance of the chamber. An electrically isolated sample holder biased to +300 V to collect the secondary electrons, connected to a digital current integrator (model 439 by Ortec) to measure the incident beam current. A home made device has been used to store the real-time evolution of the beam current in a computer file allowing the correction of the IL yields due to the current fluctuations. The target holder is a rectangle of 150 × 112 mm2 and can be tilted. The X and Y movements are controlled through stepping motors, which permits a fine control of the beam spot positioning as well as the study of several samples without venting the chamber. A silica optical fiber of 1 mm diameter fixed to the vacuum chamber, which collects the light from the scintillators

  15. Thin-film-based scintillators for hard x-ray microimaging detectors: the ScinTAX Project

    Science.gov (United States)

    Rack, A.; Cecilia, A.; Douissard, P.-A.; Dupré, K.; Wesemann, V.; Baumbach, T.; Couchaud, M.; Rochet, X.; Riesemeier, H.; Radtke, M.; Martin, T.

    2014-09-01

    The project ScinTAX developed novel thin scintillating films for the application in high performance X-ray imaging and subsequent introduced new X-ray detectors to the market. To achieve this aim lutetium orthosilicate (LSO) scintillators doped with different activators were grown successfully by liquid phase epitaxy. The high density of LSO (7.4 g/cm3), the effective atomic number (65.2) and the high light yield make this scintillator highly applicable for indirect X-ray detection in which the ionizing radiation is converted into visible light and then registered by a digital detector. A modular indirect detection system has been developed to fully exploit the potential of this thin film scintillator for radiographic and tomographic imaging. The system is compatible for high-resolution imaging with moderate dose as well as adaptable to intense high-dose applications where radiation hard microimaging detectors are required. This proceedings article shall review the achieved performances and technical details on this high-resolution detector system which is now available. A selected example application demonstrates the great potential of the optimized detector system for hard X-ray microimaging, i.e. either to improve image contrast due to the availability of efficient thin crystal films or to reduce the dose to the sample.

  16. Nanorod Array Solid State Neutron Detectors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this Phase I SBIR project, Synkera proposes to develop and commercialize solid-state neutron detectors of a unique architecture that will enable sensor modules...

  17. In-beam tests of scintillating fibre detectors at MAMI and at GSI

    CERN Document Server

    Achenbach, P; Bernauer, J C; Böhm, R; Distler, M O; Doria, L; de la Paz, M Gómez Rodríguez; Merkel, H; Müller, U; Nungesser, L; Pochodzalla, J; Majos, S Sánchez; Schlimme, B S; Walcher, Th; Weinriefer, M; Debenjak, L; Potokar, M; Sirca, S; Kavatsyuk, M; Lepyoshkina, O; Minami, S; Nakajima, D; Rappold, C; Saito, T R; Schardt, D; Träger, M; Iwase, H; Ajimura, S; Sakaguchi, A; Mizoi, Y

    2008-01-01

    The performance of scintillating fibre detectors was studied with electrons at the spectrometer facility of the Mainz microtron MAMI, as well as in a C-12 beam of 2 AGeV energy and in a beam of different particle species at GSI. Multi-anode photomultipliers were used to read out one or more bundles of 128 fibres each in different geometries. For electrons a time resolution of FWHM = 1 ns was measured in a single detector plane with a detection efficiency epsilon > 99%. A time resolution of 310 ps (FWHM) between two planes of fibres was achieved for carbon ions, leading to a FWHM = 220 ps for a single detector. The hit position residual was measured with a width of FWHM = 0.27 mm. The variation in the measured energy deposition was Delta E/E= 15-20% (FWHM) for carbon ions. In addition, the energy response to p/pi/d particles was studied. Based on the good detector performance fibre hodoscopes will be constructed for the KAOS/A1 spectrometer at MAMI and for the HypHI experiment at GSI.

  18. High-pressure plastic scintillation detector for measuring radiogenic gases in flow systems

    International Nuclear Information System (INIS)

    Radioactive gases are emitted into the atmosphere from nuclear electric power and nuclear fuel reprocessing plants, from hospitals discarding xenon used in diagnostic medicine, as well as from nuclear weapons tests. A high-pressure plastic scintillation detector was constructed to measure atmospheric levels of such radioactive gases by detecting the beta and internal conversion (IC) electron decays. Operational tests and calibrations were made that permit integration of the flow detectors into a portable Gas Analysis, Separation and Purification system (GASP). The equipment developed can be used for measuring fission gases released from nuclear reactor sources and/or as part of monitoring equipment for enforcing the Comprehensive Test Ban Treaty. The detector is being used routinely for in-line gas separation efficiency measurements, at the elevated operational pressures used for the high-pressure swing analysis system (2070 kPa) and at flow rates of 5-15 l/min . This paper presents the design features, operational methods, calibration, and detector applications

  19. High-pressure plastic scintillation detector for measuring radiogenic gases in flow systems

    International Nuclear Information System (INIS)

    Radioactive gases are emitted into the atmosphere from nuclear electric power and nuclear fuel reprocessing plants, from hospitals discarding xenon used in diagnostic medicine, as well as from nuclear weapons tests. A high-pressure plastic scintillation detector was constructed to measure atmospheric levels of such radioactive gases by detecting the beta and internal conversion (IC) electron decays. Operational tests and calibrations were made that permit integration of the flow detectors into a portable Gas Analysis, Separation and Purification system (GASP). The equipment developed can be used for measuring fission gases released from nuclear reactor sources and/or as part of monitoring equipment for enforcing the Comprehensive Test Ban Treaty. The detector is being used routinely for in-line gas separation efficiency measurements, at the elevated operational pressures used for the high-pressure swing analysis system (2070 kPa) and at flow rates of 5-15 l/min. This paper presents the design features, operational methods, calibration, and detector applications. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  20. The homestake surface-underground scintillations: Description

    Science.gov (United States)

    Corbato, S.; Daily, T.; Fenyves, E. J.; Kieda, D.; Cherry, M. L.; Lande, K.; Lee, C. K.

    1985-01-01

    Two new detectors are currently under construction at the Homestake Gold Mine a 140-ton Large Area Scintillation Detector (LASD) with an upper surface area of 130 square meters, a geometry factor (for an isotropic flux) of 1200 square meters, sr, and a depth of 4200 m.w.e.; and a surface air shower array consisting of 100 scintillator elements, each 3 square meters, spanning an area of approximately square kilometers. Underground, half of the LASD is currently running and collecting muon data; on the surface, the first section of the air shower array will begin operation in the spring of 1985. The detectors and their capabilities are described.

  1. Homestake surface-underground scintillations: description

    International Nuclear Information System (INIS)

    Two new detectors are currently under construction at the Homestake Gold Mine, a 140-ton Large Area Scintillation Detector (LASD) with an upper surface area of 130 square meters a geometry factor (for an isotropic flux) of 1200 square meters sr, and a depth of 4200 m.w.e.; and a surface air shower array consisting of 100 scintillator elements, each 3 square meters. Underground, half of the LASD is currently running and collecting muon data; on the surface, the first section of the air shower array will begin operation in the spring of 1985. The detectors and their capabilities are described

  2. Present status of sensitive detector of reactor’s antineutrinos using scintillating detectors

    Energy Technology Data Exchange (ETDEWEB)

    Fajt, L.; Mamedov, F.; Přidal, P.; Špavorová, M.; Štekl, I. [Institute of Experimental and Applied Physics, CTU in Prague (Czech Republic); Belov, V.; Egorov, V. G.; Fomina, M.; Kuznetsov, A.; Ponomarev, D.; Rozova, I.; Zhitnikov, I. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Burešová, H. [ENVINET a.s., Nuvia Group, Tǐebíč (Czech Republic)

    2015-08-17

    In 2011, the reanalysis of the reactor antineutrinos spectra led to the formulation of the Reactor Antineutrino Anomaly (RAA) [1], which indicates the discrepancy between measured and expected antineutrino fluxes on short baselines. This discrepancy appears to favor the existence of the fourth “sterile” neutrino with |Δm{sup 2}|>1 eV{sup 2}. To confirm or reject this hypothesis a high sensitive antineutrino detector located close to the reactor is required. In addition to that such a detector could be used to online monitor the isotopic composition of the reactor core and to prevent illegal production and removal of{sup 239}Pu, which is the essential part of nuclear weapons. Detector DANSSino [2] already proved that even a compact antineutrino detector (∼ 1 m{sup 3}) based on polystyrene is capable of antineutrino detection in the close vicinity of a reactor core (∼ 10 m) with signal to background ratio about one. As a common activity between JINR Dubna and IEAP CTU a new prototype of detector (called S{sup 3}) has been proposed and is under construction. The construction design, selected results of Monte Carlo simulations and results of benchmark tests are presented.

  3. Prediction and analysis of the time and energy resolution of scintillation-detectors by Monte-Carlo simulations

    International Nuclear Information System (INIS)

    A Monte-Carlo model for the emergence of scintillation-detector-signals is presented that allows for the prediction of certain scintillator-photomultiplier combinations' time and energy resolutions while relying primarily on their basic data-sheet properties like light yield, decay time, quantum efficiency, and transit time spread. At the same time the model provides a deeper understanding of the performance limiting factors and stimulates the development of improved methods for the analysis of detector output signals. The simulation results are compared to high-speed digitizer measurements of signals from a number of widely used scintillation materials like LYSO, BaF2, LaBr3, NaI, and others.

  4. Scintillator-Lucite sandwich detector for n/gamma separation in the GeV energy region

    CERN Document Server

    Watanabe, H; Harada, E; Inoue, S; Inagaki, T; Kobayashi, S; Kurilin, A S; Lim, G Y; Ogawa, I; Okuno, H; Omata, K; Sato, T; Shinkawa, T; Tsamalaidze, Z; Tsukamoto, T; Yoshimura, Y

    2002-01-01

    A Scintillator-Lucite Sandwich Detector (SLSD) has been developed for n/gamma separation in the GeV energy region. An efficient n/gamma separation is achieved by measuring a correlation between the scintillation and Cherenkov light yields. The basic performance of the detector has been tested with e, pi and p beams with momenta between 0.5 and 2.0 GeV/c; the results were compared with a Monte-Carlo simulation. The n/gamma separation capability of this detector has been studied by simulations in the energy range from 5 MeV to 12 GeV. The SLSD detector was successfully used for a beam survey of the new K sub L sup 0 beam line built for a K sub L sup 0-> pi sup 0 nu nu-bar experiment at the KEK 12-GeV proton synchrotron.

  5. Status of the digital pixel array detector for protein crystallography

    CERN Document Server

    Datte, P; Beuville, E; Endres, N; Druillole, F; Luo, L; Millaud, J E; Xuong, N H

    1999-01-01

    A two-dimensional photon counting digital pixel array detector is being designed for static and time resolved protein crystallography. The room temperature detector will significantly enhance monochromatic and polychromatic protein crystallographic through-put data rates by more than three orders of magnitude. The detector has an almost infinite photon counting dynamic range and exhibits superior spatial resolution when compared to present crystallographic phosphor imaging plates or phosphor coupled CCD detectors. The detector is a high resistivity N-type Si with a pixel pitch of 150x150 mu m, and a thickness of 300 mu m, and is bump bonded to an application specific integrated circuit. The event driven readout of the detector is based on the column architecture and allows an independent pixel hit rate above 1 million photons/s/pixel. The device provides energy discrimination and sparse data readout which yields minimal dead-time. This type of architecture allows a continuous (frameless) data acquisition, a f...

  6. Studies on the construction of a vertex detector of scintillation fibers and a multi-channel photomultiplier XP 4702

    International Nuclear Information System (INIS)

    In the last years recent attempts have been made in the development of scintillating fibers and multichannel photomultiplier tubes. A combination of these two components therefore becomes attractive in building a position sensitive detector. For this purpose some investigations were made to prove the capability of such a combination. It has been shown, that both components would be well suited for building a position sensitive detector. (orig.)

  7. Response function study of a scintillator detector of NaI(Tl); Estudo da funcao resposta de um detector cintilador de NaI(Tl)

    Energy Technology Data Exchange (ETDEWEB)

    Villa, Marcelo Barros; Costa, Alessandro Martins da, E-mail: amcosta@usp.br [Universidade de Sao Paulo (FFCLRP/USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Dept. de Fisica

    2014-07-01

    In measurements of gamma rays with Nai (Tl) scintillator, the detectors output data are pulse height spectra, that corresponding to distorted information about the radiation source due to various errors associated with the crystal scintillation process and electronics associated, instead of power spectra photons. Pulse height spectra are related to the real power spectra by means of scintillator detector response function NaI (Tl). In this work, the response function for a cylindrical crystal of Nal (Tl) of 7,62 x 7,62 cm (diameter x length) was studied, by Monte Carlo method, using the EGSnrc tool to model the transport of radiation, combined with experimental measurements. An inverse response matrix, even with the energy of the square root, which transforms the pulse height spectrum of photon energy spectrum was obtained. The results of this transformation of pulse height spectrum for photon energy spectrum is presented, showing that the methodology employed in this study is suitable.

  8. Application of digital zero-crossing technique for neutron-gamma discrimination in liquid organic scintillation detectors

    OpenAIRE

    Nakhostin, M; Walker, PM

    2010-01-01

    An algorithm for digital implementation of the zero-crossing method for n/γ discrimination in liquid organic scintillators is described. The method exhibits good performance at low energies and requires little computational effort, which makes it suitable for compact real-time neutron detectors.

  9. The Electronics and Data Acquisition Systems of a CsI(Tl) Scintillating Crystal Detector for Low Energy Neutrino Experiment

    CERN Document Server

    Lai, W P; Li, H B; Sheng, H Y; Zhuang, B A; Chang, C Y; Chen Chi Ping; Chen, Y P; Hsu, H C; Li, J; Liang, C Y; Liu, Y; Liu, Z S; Luo, C S; Shi, F; Su, R F; Teng, P K; Wang, P L; Wong, H T; Zhang, Z Y; Zhao, D X; Zhao Jia Wei; Zhao, P P; Zhou, Z Y

    2001-01-01

    A 500 kg CsI(Tl) scintillating crystal detector is under construction for the studies of low-energy neutrino physics. The requirements, design, realization and the performance of the associated electronics, trigger, data acquisition and software control systems are described. Possibilities for future extensions are discussed.

  10. A quantitative PGNAA study for use in aqueous solution measurements using Am-Be neutron source and BGO scintillation detector

    Science.gov (United States)

    Ghal-Eh, N.; Ahmadi, P.; Doost-Mohammadi, V.

    2016-02-01

    A prompt gamma neutron activation analysis (PGNAA) system including an Am-Be neutron source and BGO scintillation detector are used for quantitative analysis of bulk samples. Both Monte Carlo-simulated and experimental data are considered as input data libraries for two different procedures based on neural network and least squares methods. The results confirm the feasibility and precision of the proposed methods.

  11. Integrated Miniature Arrays of Optical Biomolecule Detectors

    Science.gov (United States)

    Iltchenko, Vladimir; Maleki, Lute; Lin, Ying; Le, Thanh

    2009-01-01

    Integrated miniature planar arrays of optical sensors for detecting specific biochemicals in extremely small quantities have been proposed. An array of this type would have an area of about 1 cm2. Each element of the array would include an optical microresonator that would have a high value of the resonance quality factor (Q . 107). The surface of each microresonator would be derivatized to make it bind molecules of a species of interest, and such binding would introduce a measurable change in the optical properties of the microresonator. Because each microresonator could be derivatized for detection of a specific biochemical different from those of the other microresonators, it would be possible to detect multiple specific biochemicals by simultaneous or sequential interrogation of all the elements in the array. Moreover, the derivatization would make it unnecessary to prepare samples by chemical tagging. Such interrogation would be effected by means of a grid of row and column polymer-based optical waveguides that would be integral parts of a chip on which the array would be fabricated. The row and column polymer-based optical waveguides would intersect at the elements of the array (see figure). At each intersection, the row and column waveguides would be optically coupled to one of the microresonators. The polymer-based waveguides would be connected via optical fibers to external light sources and photodetectors. One set of waveguides and fibers (e.g., the row waveguides and fibers) would couple light from the sources to the resonators; the other set of waveguides and fibers (e.g., the column waveguides and fibers) would couple light from the microresonators to the photodetectors. Each microresonator could be addressed individually by row and column for measurement of its optical transmission. Optionally, the chip could be fabricated so that each microresonator would lie inside a microwell, into which a microscopic liquid sample could be dispensed.

  12. Radiation hardness of plastic scintillators for the Tile Calorimeter of the ATLAS detector

    Science.gov (United States)

    Jivan, H.; Sideras-Haddad, E.; Erasmus, R.; Liao, S.; Madhuku, M.; Peters, G.; Sekonya, K.; Solvyanov, O.

    2015-10-01

    The radiation damage in polyvinyl toluene based plastic scintillator EJ200 obtained from ELJEN technology was investigated. This forms part of a comparative study conducted to aid in the upgrade of the Tile Calorimeter of the ATLAS detector during which the Gap scintillators will be replaced. Samples subjected to 6 MeV proton irradiation using the tandem accelerator of iThemba LABS, were irradiated with doses of approximately 0.8 MGy, 8 MGy, 25 MGy and 80 MGy. The optical properties were investigated using transmission spectroscopy and light yield analysis whilst structural damage was assessed using Raman spectroscopy. Findings indicate that for the dose of 0.8 MGy, no structural damage occurs and light loss can be attributed to a breakdown in the light transfer between base and fluor dopants. For doses of 8 MGy to 80 MGy, structural damage leads to possible hydrogen loss in the benzene ring of the PVT base which forms free radicals. This results in an additional absorptive component causing increased transmission loss and light yield loss with increasing dose.

  13. AIGO: a southern hemisphere detector for the worldwide array of ground-based interferometric gravitational wave detectors

    Energy Technology Data Exchange (ETDEWEB)

    Barriga, P; Blair, D G; Coward, D; Davidson, J; Dumas, J-C; Howell, E; Ju, L; Wen, L; Zhao, C [School of Physics, The University of Western Australia, Crawley, WA 6009 (Australia); McClelland, D E; Scott, S M; Slagmolen, B J J; Inta, R [Department of Physics, Faculty of Science, Australian National University, Canberra, ACT 0200 (Australia); Munch, J; Ottaway, D J; Veitch, P; Hosken, D [Department of Physics, University of Adelaide, Adelaide, SA 5005 (Australia); Melatos, A; Chung, C; Sammut, L, E-mail: pbarriga@cyllene.uwa.edu.a [School of Physics University of Melbourne, Parkville, Vic 3010 (Australia)

    2010-04-21

    This paper describes the proposed AIGO detector for the worldwide array of interferometric gravitational wave detectors. The first part of the paper summarizes the benefits that AIGO provides to the worldwide array of detectors. The second part gives a technical description of the detector, which will follow closely the Advanced LIGO design. Possible technical variations in the design are discussed.

  14. The Indiana silicon sphere 4{pi} charged-particle detector array

    Energy Technology Data Exchange (ETDEWEB)

    Kwiatkowski, K. [Indiana Univ., Bloomington, IN (United States). Dept. of Chem. and Phys. and IUCF; Bracken, D.S. [Indiana Univ., Bloomington, IN (United States). Dept. of Chem. and Phys. and IUCF; Morley, K.B. [Indiana Univ., Bloomington, IN (United States). Dept. of Chem. and Phys. and IUCF; Brzychczyk, J. [Indiana Univ., Bloomington, IN (United States). Dept. of Chem. and Phys. and IUCF; Renshaw Foxford, E. [Indiana Univ., Bloomington, IN (United States). Dept. of Chem. and Phys. and IUCF; Komisarcik, K. [Indiana Univ., Bloomington, IN (United States). Dept. of Chem. and Phys. and IUCF; Viola, V.E. [Indiana Univ., Bloomington, IN (United States). Dept. of Chem. and Phys. and IUCF; Yoder, N.R. [Indiana Univ., Bloomington, IN (United States). Dept. of Chem. and Phys. and IUCF; Dorsett, J. [Department of Chemistry Technical Services, Indiana University, Bloomington, IN 47405 (United States); Poehlman, J. [Department of Chemistry Technical Services, Indiana University, Bloomington, IN 47405 (United States); Madden, N. [Consultant, Livermore, CA (United States); Ottarson, J. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824 (United States)

    1995-06-15

    A low threshold charged particle detector array for the study of fragmentation processes in light-ion-induced reactions has been constructed and successfully implemented at the IUCF and Saturne II accelerators. The array consists of 162-triple-element detector telescopes mounted in a spherical geometry and covering 74% of 4{pi} in solid angle. Telescope elements are composed of (1) an axial-field gas ionization chamber operated with C{sub 3}F{sub 8} gas; (2) a 0.5 mm thick passivated silicon detector, and (3) a 2.8 cm thick CsI(Tl) scintillation crystal with photodiode readout. Discrete element identification is obtained for ejectiles up to Z similar 16 over the dynamic range 0.7{<=}E/A{<=}95 MeV/nucleon. Isotopes are also distinguished for H, He, Li and Be ejectiles with 8< or {approx}E/A< or {approx}95 MeV. Custom-designed electronics are employed for bias supplies and linear signal processing. Data are acquired via a CAMAC/VME/Ethernet system. (orig.).

  15. Electronics and data acquisition system of the extensive air shower detector array at the University of Puebla

    Science.gov (United States)

    Perez, E.; Salazar, H.; Villasenor, L.; Martinez, O.; Conde, R.; Murrieta, T.

    Field programmable gate arrays (FPGAs) are playing an increasing role in DAQ systems in cosmic ray experiments due to their high speed and integration and their low cost and low power comsumption. In this paper we describe in detail the new electronics and data acquisition system based on FPGA boards of the extensive air shower detector array built in the Campus of the University of Puebla. The purpose of this detector array is to measure the energy and arrival direction of primary cosmic rays with energies around 1015 eV. The array consists of 10 liquid scintillator detectors and 6 water Cherenkov detectors (of 1.86 m2 cross section), distributed in a square grid with a detector spacing of 20 m over an area of 4000 m2. The electronics described also makes use of analog to digital converters with a resolution of 10 bits and sampling speeds of 100 MS/s to digitize the PMT signals. We also discuss the advantages of discriminating the PMT signals inside the FPGAs with respect to the conventional use of dedicated discrimination circuits.

  16. Photon counting detector array algorithms for deep space optical communications

    Science.gov (United States)

    Srinivasan, Meera; Andrews, Kenneth S.; Farr, William H.; Wong, Andre

    2016-03-01

    For deep-space optical communications systems utilizing an uplink optical beacon, a single-photon-counting detector array on the flight terminal can be used to simultaneously perform uplink tracking and communications as well as accurate downlink pointing at photon-starved (pW=m2) power levels. In this paper, we discuss concepts and algorithms for uplink signal acquisition, tracking, and parameter estimation using a photon-counting camera. Statistical models of detector output data and signal processing algorithms are presented, incorporating realistic effects such as Earth background and detector/readout blocking. Analysis and simulation results are validated against measured laboratory data using state-of-the-art commercial photon-counting detector arrays, demonstrating sub-microradian tracking errors under channel conditions representative of deep space optical links.

  17. The Detector Calibration System for the CUORE cryogenic bolometer array

    CERN Document Server

    Cushman, J S; Davis, C J; Ejzak, L; Lenz, D; Lim, K E; Heeger, K M; Maruyama, R H; Nucciotti, A; Sangiorgio, S; Wise, T

    2016-01-01

    The Cryogenic Underground Observatory for Rare Events (CUORE) is a ton-scale cryogenic experiment designed to search for neutrinoless double-beta decay of $^{130}$Te and other rare events. The CUORE detector consists of 988 TeO$_2$ bolometers operated underground at 10~mK in a dilution refrigerator at the Laboratori Nazionali del Gran Sasso. Candidate events are identified through a precise measurement of their energy. The absolute energy response of the detectors is established by the regular calibration of each individual bolometer using gamma sources. The close-packed configuration of the CUORE bolometer array combined with the extensive shielding surrounding the detectors requires the placement of calibration sources within the array itself. The CUORE Detector Calibration System is designed to insert radioactive sources into and remove them from the cryostat while respecting the stringent heat load, radiopurity, and operational requirements of the experiment. This paper describes the design, commissioning...

  18. High-energy interactions in Kinetic Inductance Detectors arrays

    CERN Document Server

    D'Addabbo, A; Goupy, J; Benoit, A; Bourrion, O; Catalano, A; Macias-Perez, J F; Monfardini, A

    2015-01-01

    The impacts of Cosmic Rays on the detectors are a key problem for space-based missions. We are studying the effects of such interactions on arrays of Kinetic Inductance Detectors (KID), in order to adapt this technology for use on board of satellites. Before proposing a new technology such as the Kinetic Inductance Detectors for a space-based mission, the problem of the Cosmic Rays that hit the detectors during in-flight operation has to be studied in detail. We present here several tests carried out with KID exposed to radioactive sources, which we use to reproduce the physical interactions induced by primary Cosmic Rays, and we report the results obtained adopting different solutions in terms of substrate materials and array geometries. We conclude by outlining the main guidelines to follow for fabricating KID for space-based applications.

  19. Development of a gadolinium-loaded liquid scintillator for the Hanaro short baseline prototype detector

    Science.gov (United States)

    Yeo, In Sung; Joo, Kyung Kwang; So, Sun Heang; Song, Sook Hyung; Kim, Hong Joo; So, Jung Ho; Park, Kang Soon; Ma, Kyung Ju; Jeon, Eun Ju; Kim, Jin Yu; Kim, Young Duk; Lee, Jason; Lee, Jeong-Yeon; Sun, Gwang-Min

    2014-02-01

    We propose a new experiment on the site of the Korea Atomic Energy Research Institute (KAERI) located at Daejeon, Korea. The Hanaro short baseline (SBL) nuclear reactor with a thermal power output 30 MW is used to investigate a reactor neutrino anomaly. A Hanaro SBL prototype detector having a 60- l volume has been constructed ˜6 m away from the reactor core. A gadolinium (Gd)-loaded liquid scintillator (LS) is used as an active material to trigger events. The selection of the LS is guided by physical and technical requirements, as well as safety considerations. A linear alkyl benzene (LAB) is used as a base solvent of the Hanaro SBL prototype detector. Three g/ l of PPO and 30 mg/ l of bis-MSB are dissolved to formulate the LAB-based LS. Then, a 0.5% gadolinium (Gd) complex with carboxylic acid is loaded into the LAB-based LS by using the liquidliquid extraction method. In this paper, we will summarize all the characteristics of the Gd-loaded LAB-based LS for the Hanaro prototype detector.

  20. A practical method for depth of interaction determination in monolithic scintillator PET detectors.

    Science.gov (United States)

    van Dam, Herman T; Seifert, Stefan; Vinke, Ruud; Dendooven, Peter; Löhner, Herbert; Beekman, Freek J; Schaart, Dennis R

    2011-07-01

    Several new methods for determining the depth of interaction (DOI) of annihilation photons in monolithic scintillator detectors with single-sided, multi-pixel readout are investigated. The aim is to develop a DOI decoding method that allows for practical implementation in a positron emission tomography system. Specifically, calibration data, obtained with perpendicularly incident gamma photons only, are being used. Furthermore, neither detector modifications nor a priori knowledge of the light transport and/or signal variances is required. For this purpose, a clustering approach is utilized in combination with different parameters correlated with the DOI, such as the degree of similarity to a set of reference light distributions, the measured intensity on the sensor pixel(s) closest to the interaction position and the peak intensity of the measured light distribution. The proposed methods were tested experimentally on a detector comprised of a 20 mm × 20 mm × 12 mm polished LYSO:Ce crystal coupled to a 4 × 4 multi-anode photomultiplier. The method based on the linearly interpolated measured intensities on the sensor pixels closest to the estimated (x, y)-coordinate outperformed the other methods, yielding DOI resolutions between ∼1 and ∼4.5 mm FWHM depending on the DOI, the (x, y) resolution and the amount of reference data used. PMID:21693789

  1. A practical method for depth of interaction determination in monolithic scintillator PET detectors

    International Nuclear Information System (INIS)

    Several new methods for determining the depth of interaction (DOI) of annihilation photons in monolithic scintillator detectors with single-sided, multi-pixel readout are investigated. The aim is to develop a DOI decoding method that allows for practical implementation in a positron emission tomography system. Specifically, calibration data, obtained with perpendicularly incident gamma photons only, are being used. Furthermore, neither detector modifications nor a priori knowledge of the light transport and/or signal variances is required. For this purpose, a clustering approach is utilized in combination with different parameters correlated with the DOI, such as the degree of similarity to a set of reference light distributions, the measured intensity on the sensor pixel(s) closest to the interaction position and the peak intensity of the measured light distribution. The proposed methods were tested experimentally on a detector comprised of a 20 mm x 20 mm x 12 mm polished LYSO:Ce crystal coupled to a 4 x 4 multi-anode photomultiplier. The method based on the linearly interpolated measured intensities on the sensor pixels closest to the estimated (x, y)-coordinate outperformed the other methods, yielding DOI resolutions between ∼1 and ∼4.5 mm FWHM depending on the DOI, the (x, y) resolution and the amount of reference data used.

  2. LHCb: The Front-End electronics for the LHCb scintillating fibres detector

    CERN Multimedia

    Chanal, H; Pillet, N

    2014-01-01

    The LHCb detector will be upgraded during the next LHC shutdown in 2018/19. The tracker system will have a major overhaul. Its components will be replaced with new technologies in order to cope with the increased hit occupancy and radiation environment. A detector made of scintillating fibres read out by silicon photomultipliers (SiPM) is studied for this upgrade. Even if this technology has proven to achieve high efficiency and spatial resolution, its integration within a LHC experiment bears new challenges. This detector will consist of 12 planes of 5 to 6 layers of 250 $\\mu$m fibres with an area of 5×6 m$^2$. Its lead to a total of 500k SiPM channels which need to will be read out at 40MHz. This talk gives an overview of the R&D status of the readout board and the PACIFIC chip. The readout board is connected to the SiPM on one side and to the experiment data-acquisition, experimental control system and services on the other side . The PACIFIC chip is a 128 channel ASIC which can be connected to one 12...

  3. Development of a gadolinium-loaded liquid scintillator for the Hanaro short baseline prototype detector

    International Nuclear Information System (INIS)

    We propose a new experiment on the site of the Korea Atomic Energy Research Institute (KAERI) located at Daejeon, Korea. The Hanaro short baseline (SBL) nuclear reactor with a thermal power output 30 MW is used to investigate a reactor neutrino anomaly. A Hanaro SBL prototype detector having a 60-l volume has been constructed ∼6 m away from the reactor core. A gadolinium (Gd)-loaded liquid scintillator (LS) is used as an active material to trigger events. The selection of the LS is guided by physical and technical requirements, as well as safety considerations. A linear alkyl benzene (LAB) is used as a base solvent of the Hanaro SBL prototype detector. Three g/l of PPO and 30 mg/l of bis-MSB are dissolved to formulate the LAB-based LS. Then, a 0.5% gadolinium (Gd) complex with carboxylic acid is loaded into the LAB-based LS by using the liquid - liquid extraction method. In this paper, we will summarize all the characteristics of the Gd-loaded LAB-based LS for the Hanaro prototype detector.

  4. The Front-End electronics for the LHCb scintillating fibres detector

    CERN Document Server

    Chanal, Hervé; Pillet, Nicolas

    2014-01-01

    The LHCb detector will be upgraded during the next LHC shutdown in 2018/19 [ 1 ]. The tracker system will have a major overhaul. Its components will be replaced with new technologies in order to cope with the increased hit occupancy and radiation environment. A detector made of scintillating fibres read out by silicon photomultipliers (SiPM) is studied for this upgrade. Even if this technology has proven to achieve high efficiency and spatial resolution, its integration within a LHC experiment bears new challenges. This detector will consist of 12 planes of 5 to 6 layers of 250 m m fibres with an area of 5 6 m 2 . It leads to a total of 500k SiPM channels which need to be read out at 40 MHz. This article gives an overview of the R&D; status of the readout board and the PACIFIC chip. The readout board is connected to the SiPM on one side and to the experiment data-acquisition, experimental control system and services on the other side. The PACIFIC chip is a 128-channels ASIC which can be connected to one 1...

  5. Digital Data Acquisition For the Low Energy Neutron Detector Array (LENDA)

    CERN Document Server

    Lipschutz, S; Hill, J; Liddick, S N; Noji, S; Prokop, C J; Scott, M; Solt, M; Sullivan, C; Tompkins, J

    2016-01-01

    A digital data acquisition system (DDAS) has been implemented for the Low Energy Neutron Detector Array (LENDA). LENDA is an array of 24 BC-408 plastic-scintillator bars designed to measure low-energy neutrons with kinetic energies in the range of 100 keV to 10 MeV from (p,n)-type charge-exchange reactions. Compared to the previous data acquisition (DAQ) system for LENDA, DDAS offers the possibility to lower the neutron detection threshold, increase the overall neutron-detection efficiency, decrease the dead time of the system, and allow for easy expansion of the array. The system utilized in this work was XIA's Digital Gamma Finder Pixie-16 250 MHz digitizers. A detector-limited timing resolution of 400 ps was achieved for a single LENDA bar. Using DDAS, the neutron detection threshold of the system was reduced compared to the previous analog system, now reaching below 100 keV. The new DAQ system was successfully used in a recent charge-exchange experiment using the $^{16}$C(p,n) reaction at the National Sup...

  6. Scintillation particle detection based on microfluidics

    CERN Document Server

    Mapelli, A; Renaud, P; Gorini, B; Trivino, N Vico; Jiguet, S; Vandelli, W; Haguenauer, M

    2010-01-01

    A novel type of particle detector based on scintillation, with precise spatial resolution and high radiation hardness, is being studied. It consists of a single microfluidic channel filled with a liquid scintillator and is designed to define an array of scintillating waveguides each independently coupled to a photodetector. Prototype detectors built using an SU-8 epoxy resin have been tested with electrons from a radioactive source. The experimental results show a light yield compatible with the theoretical expectations and confirm the validity of the approach. (C) 2010 Elsevier B.V. All rights reserved.

  7. ecCNO solar neutrinos: A challenge for gigantic ultra-pure liquid scintillator detectors

    Science.gov (United States)

    Villante, F. L.

    2015-03-01

    Neutrinos produced in the Sun by electron capture reactions on 13N, 15O and 17F, to which we refer as ecCNO neutrinos, are not usually considered in solar neutrino analysis since the expected fluxes are extremely low. The experimental determination of this sub-dominant component of the solar neutrino flux is very difficult but could be rewarding since it provides a determination of the metallic content of the solar core and, moreover, probes the solar neutrino survival probability in the transition region at Eν ∼ 2.5 MeV. In this Letter, we suggest that this difficult measure could be at reach for future gigantic ultra-pure liquid scintillator detectors, such as LENA.

  8. Measurement-based characterization of multipixel avalanche photodiodes for scintillating detectors

    CERN Document Server

    Dziewiecki, M

    2012-01-01

    Multipixel avalanche photodiodes (MAPD) are recently gaining popularity in high energy physics experiments as an attractive replacement for photomultiplier tubes, which have been extensively used for many years as a part of various scintillating detectors. Their low price, small dimensions and another features facilitating their use (like mechanical shock resistance, magnetic field immunity or moderate supply voltage) make the MAPDs a good choice for commercial use as well, what is reflected in growing number of producers as well as MAPD models available on the market. This dissertation presents Author’s experience with MAPD measurements and modelling, gained during his work on the T2K (Tokai-to-Kamioka) long-baseline neutrino experiment, carried out by an international collaboration in Japan. First, operation principle of the MAPD, definitions of various parameters and measurement methods are discussed. Then, a device for large-scale MAPD measurements and related data processing methods are described. Fina...

  9. Borexino A real time liquid scintillator detector for low energy solar neutrino study

    CERN Document Server

    Miramonti, L

    2002-01-01

    Borexino is a large unsegmented calorimeter featuring 300 tons of liquid scintillator, contained in a 8.5 meter nylon vessel, viewed by 2200 PMTs. The main goal of Borexino is the study, in real time, of low energy solar neutrinos, and in particular, the monoenergetic neutrinos coming from $^7Be$, which is one of the missing links on the solar neutrino problem. The achievement of high radiopurity level, in the order of $10^{-16} g/g$ of U/Th equivalent, necessary to the detection of the low energy component of the solar neutrino flux, was proved in the Borexino prototype: the Counting Test Facility. The detector is located underground in the Laboratori Nazionali del Gran Sasso in the center of Italy at 3500 meter water equivalent depth. In this paper the science and technology of Borexino are reviewed and its main capabilities are presented.

  10. Time and position sensitive single photon detector for scintillator read-out

    Science.gov (United States)

    Schössler, S.; Bromberger, B.; Brandis, M.; Schmidt, L. Ph H.; Tittelmeier, K.; Czasch, A.; Dangendorf, V.; Jagutzki, O.

    2012-02-01

    We have developed a photon counting detector system for combined neutron and γ radiography which can determine position, time and intensity of a secondary photon flash created by a high-energy particle or photon within a scintillator screen. The system is based on a micro-channel plate photomultiplier concept utilizing image charge coupling to a position- and time-sensitive read-out anode placed outside the vacuum tube in air, aided by a standard photomultiplier and very fast pulse-height analyzing electronics. Due to the low dead time of all system components it can cope with the high throughput demands of a proposed combined fast neutron and dual discrete energy γ radiography method (FNDDER). We show tests with different types of delay-line read-out anodes and present a novel pulse-height-to-time converter circuit with its potential to discriminate γ energies for the projected FNDDER devices for an automated cargo container inspection system (ACCIS).

  11. Time and position sensitive single photon detector for scintillator read-out

    CERN Document Server

    Schössler, Sven; Brandis, Michal; Schmidt, Lothar Ph H; Tittelmeier, Kai; Czasch, Achim; Dangendorf, Volker; Jagutzki, Ottmar

    2012-01-01

    We have developed a photon counting detector system for combined neutron and gamma radiography which can determine position, time and intensity of a secondary photon flash created by a high-energy particle or photon within a scintillator screen. The system is based on a micro-channel plate photomultiplier concept utilizing image charge coupling to a position- and time-sensitive read-out anode placed outside the vacuum tube in air, aided by a standard photomultiplier and very fast pulse-height analyzing electronics. Due to the low dead time of all system components it can cope with the high throughput demands of a proposed combined fast neutron and dual discrete energy gamma radiography method (FNDDER). We show tests with different types of delay-line read-out anodes and present a novel pulse-height-to-time converter circuit with its potential to discriminate gamma energies for the projected FNDDER devices for an automated cargo container inspection system (ACCIS).

  12. HgCdTe e-avalanche photodiode detector arrays

    OpenAIRE

    Anand Singh; Shukla, A. K.; Ravinder Pal

    2015-01-01

    Initial results on the MWIR e-APD detector arrays with 30 μm pitch fabricated on LPE grown compositionally graded p-HgCdTe epilayers are presented. High dynamic resistance times active area (R0A) product 2 × 106 Ω-cm2, low dark current density 4 nA/cm2 and high gain 5500 at -8 V were achieved in the n+-υ-p+ HgCdTe e-APD at 80 K. LPE based HgCdTe e-APD development makes this technology amenable for adoption in the foundries established for the conventional HgCdTe photovoltaic detector arrays w...

  13. Conference on physics from large {gamma}-ray detector arrays

    Energy Technology Data Exchange (ETDEWEB)

    The conference on {open_quotes}Physics from Large {gamma}-ray Detector Arrays{close_quotes} is a continuation of the series of conferences that have been organized every two years by the North American Heavy-ion Laboratories. The aim of the conference this year was to encourage discussion of the physics that can be studied with such large arrays. This volume is the collected proceedings from this conference. It discusses properties of nuclear states which can be created in heavy-ion reactions, and which can be observed via such detector systems.

  14. n/γ Pulse shape discrimination comparison of EJ301 and EJ339A liquid scintillation detectors

    International Nuclear Information System (INIS)

    Highlights: • We model the optical process in liquid scintillator with Geant4 simulation toolkit. • We combine the optical process and the PMT response to simulate anode signal. • We performed experiments to benchmark the simulation results. • EJ301 and EJ339A are both good for PSD from simulation and experiment results. • EJ301 has a better PSD feature than EJ339A. - Abstract: In this work, we evaluated the neutron-gamma discrimination capability of EJ301 and EJ339A liquid scintillation detectors via the pulse shape discrimination (PSD) method. Both simulation and experimental results are reported. The Geant4 simulation toolkit was used to model the scintillation process inside the scintillator, for neutron and gamma events, respectively. For the experiments, a high-speed digitizer was used to acquire data, which was then processed in MATLAB. This work compared the PSD performance of two liquid scintillation detectors and demonstrated the capability of Geant4 with regard to simulation of pulse shape

  15. Advanced ACTPol Cryogenic Detector Arrays and Readout

    CERN Document Server

    Henderson, S W; Austermann, J; Baildon, T; Battaglia, N; Beall, J A; Becker, D; De Bernardis, F; Bond, J R; Calabrese, E; Choi, S K; Coughlin, K P; Crowley, K T; Datta, R; Devlin, M J; Duff, S M; Dunner, R; Dunkley, J; van Engelen, A; Gallardo, P A; Grace, E; Hasselfield, M; Hills, F; Hilton, G C; Hincks, A D; Hlozek, R; Ho, S P; Hubmayr, J; Huffenberger, K; Hughes, J P; Irwin, K D; Koopman, B J; Kosowsky, A B; Li, D; McMahon, J; Munson, C; Nati, F; Newburgh, L; Niemack, M D; Niraula, P; Page, L A; Pappas, C G; Salatino, M; Schillaci, A; Schmitt, B L; Sehgal, N; Sherwin, B D; Sievers, J L; Simon, S M; Spergel, D N; Staggs, S T; Stevens, J R; Thornton, R; Van Lanen, J; Vavagiakis, E M; Ward, J T; Wollack, E J

    2015-01-01

    Advanced ACTPol is a polarization-sensitive upgrade for the 6 m aperture Atacama Cosmology Telescope (ACT), adding new frequencies and increasing sensitivity over the previous ACTPol receiver. In 2016, Advanced ACTPol will begin to map approximately half the sky in five frequency bands (28-230 GHz). Its maps of primary and secondary cosmic microwave background (CMB) anisotropies -- imaged in intensity and polarization at few arcminute-scale resolution -- will enable precision cosmological constraints and also a wide array of cross-correlation science that probes the expansion history of the universe and the growth of structure via gravitational collapse. To accomplish these scientific goals, the Advanced ACTPol receiver will be a significant upgrade to the ACTPol receiver, including four new multichroic arrays of cryogenic, feedhorn-coupled AlMn transition edge sensor (TES) polarimeters (fabricated on 150 mm diameter wafers); a system of continuously rotating meta-material silicon half-wave plates; and a new ...

  16. Development of neutron-monitor detector using liquid organic scintillator coupled with 6Li + ZnS(Ag) Sheet.

    Science.gov (United States)

    Sato, Tatsuhiko; Endo, Akira; Yamaguchi, Yasuhiro; Takahashi, Fumiaki

    2004-01-01

    A phoswitch-type detector has been developed for monitoring neutron doses in high-energy accelerator facilities. The detector is composed of a liquid organic scintillator (BC501A) coupled with ZnS(Ag) sheets doped with 6Li. The dose from neutrons with energies above 1 MeV is evaluated from the light output spectrum of the BC501A by applying the G-function, which relates the spectrum to the neutron dose directly. The dose from lower energy neutrons, on the other hand, is estimated from the number of scintillations emitted from the ZnS(Ag) sheets. Characteristics of the phoswitch-type detector were studied experimentally in some neutron fields. It was found from the experiments that the detector has an excellent property of pulse-shape discrimination between the scintillations of BC501A and the ZnS(Ag) sheets. The experimental results also indicate that the detector is capable of reproducing doses from thermal neutrons as well as neutrons with energies from one to several tens of megaelectronvolts (MeV).

  17. Measurements and elimination of Cherenkov light in fiber-optic scintillating detector for electron beam therapy dosimetry

    International Nuclear Information System (INIS)

    In this study, a miniature fiber-optic radiation detector has been developed using a water-equivalent organic scintillator for electron beam therapy dosimetry. Usually, two kinds of light signals such as fluorescent and Cherenkov lights are generated in a fiber-optic radiation detector when a high-energy electron beam is irradiated. The fluorescent light signal is produced in the scintillator and is transmitted through a plastic optical fiber to a remote light-measuring device such as a PMT or a photodiode. The Cherenkov light could be also produced in the plastic optical fiber itself and be detected by a light-measuring device. Therefore, it could cause problems or limit the accuracy of the detection of a fluorescent light signal that is proportional to dose. The objectives of this study are to measure, characterize and eliminate Cherenkov light generated in a plastic optical fiber used as a component of a fiber-optic radiation detector and to detect a real fluorescent light signal from the scintillator. In this study, the intensity of Cherenkov light is measured and characterized as a function of the incident angle of an electron beam from a LINAC, as a function of the electron beam energy, and as a function of electron beam size. Also, a subtraction method using a background optical fiber without a scintillator and an optical discrimination method using optical filters are investigated to remove Cherenkov light

  18. A gated liquid-scintillator-based neutron detector for fast-ignitor experiments and down-scattered neutron measurements

    International Nuclear Information System (INIS)

    The detection of neutrons in fast-ignitor experiments or down-scattered neutrons in inertial fusion experiments is very challenging since it requires the neutron detection system to recover within 10-100 ns from a high background orders of magnitude stronger than the signal of interest. The background is either the hard x-ray emission from short-pulse laser target interactions for the fast-ignitor experiments or the primary neutron signal for the down-scattered neutrons. A liquid-scintillator detector has been developed using a gated photomultiplier that suppresses the background signal and eliminates the afterglow present in conventional plastic scintillators.

  19. Monolithic arrays of silicon drift detectors for medical imaging applications and related CMOS readout electronics

    Energy Technology Data Exchange (ETDEWEB)

    Fiorini, C. [Politecnico di Milano, Dipartimento di Elettronica e Informazione, Milan (Italy) and INFN, Sezione di Milano, Milan (Italy)]. E-mail: carlo.fiorini@polimi.it; Longoni, A. [Politecnico di Milano, Dipartimento di Elettronica e Informazione, Milan (Italy); INFN, Sezione di Milano, Milan (Italy); Porro, M. [Politecnico di Milano, Dipartimento di Ingegneria Nucleare, Milan (Italy); INFN, Sezione di Milano, Milan (Italy); Perotti, F. [Istituto di Astrofisica Spaziale e Fisica Cosmica - INAF, Milan (Italy); Lechner, P. [PNSensors, Munich (Germany); Strueder, L. [MPI fuer Extraterrestrische Physik Halbleiterlabor, Munich (Germany)

    2006-05-01

    Monolithic arrays of Silicon Drift Detectors (SDDs) have been recently proposed to be used with scintillators for high-position-resolution {gamma}-ray imaging applications. Thanks to the low electronics noise due to the small value of the output capacitance, the SDD offers better performances with respect to conventional photodiodes of the same geometry. We show the results achieved with a small monolithic array of SDDs, each one with a front-end JFET integrated at its center, used as photodetector in a first prototype of Anger Camera. An intrinsic resolution better than 200 {mu}m has been achieved with this prototype. Moreover, we describe a new monolithic array of SDDs composed of 77 single hexagonal units, each one with an active area of 8.7 mm{sup 2}, for a total active area of the device of 6.7 cm{sup 2}. Finally, the basic principles and the first results of the CMOS readout chip specifically designed for the readout of the signals from SDDs arrays are presented.

  20. Monolithic arrays of silicon drift detectors for medical imaging applications and related CMOS readout electronics

    International Nuclear Information System (INIS)

    Monolithic arrays of Silicon Drift Detectors (SDDs) have been recently proposed to be used with scintillators for high-position-resolution γ-ray imaging applications. Thanks to the low electronics noise due to the small value of the output capacitance, the SDD offers better performances with respect to conventional photodiodes of the same geometry. We show the results achieved with a small monolithic array of SDDs, each one with a front-end JFET integrated at its center, used as photodetector in a first prototype of Anger Camera. An intrinsic resolution better than 200 μm has been achieved with this prototype. Moreover, we describe a new monolithic array of SDDs composed of 77 single hexagonal units, each one with an active area of 8.7 mm2, for a total active area of the device of 6.7 cm2. Finally, the basic principles and the first results of the CMOS readout chip specifically designed for the readout of the signals from SDDs arrays are presented

  1. The First Tests of a Large-Area Light Detector Equipped with Metallic Magnetic Calorimeters for Scintillating Bolometers for the LUMINEU Neutrinoless Double Beta Decay Search

    Science.gov (United States)

    Gray, D.; Enss, C.; Fleischmann, A.; Gastaldo, L.; Hassel, C.; Hengstler, D.; Kempf, S.; Loidl, M.; Navick, X. F.; Rodrigues, M.

    2016-08-01

    Future rare-event searches using scintillating crystals need very low background levels for high sensitivity; however, unresolved pile-up can limit this. We present the design and fabrication of large-area photon detectors based on metallic magnetic calorimeters (MMCs), optimized for fast rise times to resolve close pile-up. The first prototypes have been characterized using Fe-55 X-rays and ZnMoO4 crystal scintillation light. A fast intrinsic rise time of 25-30 \\upmu s has been measured and has been compared to the 250 \\upmu s scintillation light pulse rise time constant. The difference indicates that the scintillation process limits the light pulse rise time. The fast rise time allows for a reduction of background due to close pile-up events as well as the study of the inherent crystal scintillation process. MMC-based photon detectors are shown to be a promising tool for scintillating crystal based rare event searches.

  2. Conceptual design of a hybrid Ge:Ga detector array

    Science.gov (United States)

    Parry, C. M.

    1984-01-01

    For potential applications in space infrared astronomy missions such as the Space Infrared Telescope Facility and the Large Deployable Reflector, integrated arrays of long-wavelength detectors are desired. The results of a feasibility study which developed a design for applying integrated array techniques to a long-wavelength (gallium-doped germanium) material to achieve spectral coverage between 30 and 200 microns are presented. An approach which builds up a two-dimensional array by stacking linear detector modules is presented. The spectral response of the Ge:Ga detectors is extended to 200 microns by application of uniaxial stress to the stack of modules. The detectors are assembled with 1 mm spacing between the elements. Multiplexed readout of each module is accomplished with integration sampling of a metal-oxide-semiconductor (MOS) switch chip. Aspects of the overall design, including the anticipated level of particle effects on the array in the space environment, a transparent electrode design for 200 microns response, estimates of optical crosstalk, and mechanical stress design calculations are included.

  3. Conceptual design for a high resolution vertex detector for charm and beauty experiments using scintillating fibre optics

    International Nuclear Information System (INIS)

    The authors consider a detector, using scintillating optical fibres, designed to directly detect the production and decay vertices of charm and beauty particles. The aim is to provide a detector which can be used in a fixed target spectrometer to achieve sensitivities in the range 10 - 100 events per nanobarn. With a simple change in geometry the same technique should also allow the search for and study of heavy flavour production in a colliding beam machine and hence perhaps a route towards the Higgs particle. First the ideas for a fixed target detector, are discussed and then the collider development. (author)

  4. DANSS: Detector of the reactor AntiNeutrino based on Solid Scintillator

    CERN Document Server

    Alekseev, I; Brudanin, V; Danilov, M; Egorov, V; Filosofov, D; Fomina, M; Hons, Z; Kazartsev, S; Kobyakin, A; Kuznetsov, A; Machikhiliyan, I; Medvedev, D; Nesterov, V; Olshevsky, A; Ponomarev, D; Rozova, I; Rumyantseva, N; Rusinov, V; Salamatin, A; Shevchik, Ye; Shirchenko, M; Shitov, Yu; Skrobova, N; Starostin, A; Svirida, D; Tarkovsky, E; Tikhomirov, I; Vlasek, J; Zhitnikov, I; Zinatulina, D

    2016-01-01

    The DANSS project is aimed at creating a relatively compact neutrino spectrometer which does not contain any flammable or other dangerous liquids and may therefore be located very close to the core of an industrial power reactor. As a result, it is expected that high neutrino flux would provide about 15,000 IBD interactions per day in the detector with a sensitive volume of 1 m$^3$. High segmentation of the plastic scintillator will allow to suppress a background down to a 1% level. Numerous tests performed with a simplified pilot prototype DANSSino under a 3 GW$_{th}$ reactor of the Kalinin NPP have demonstrated operability of the chosen design. The DANSS detector surrounded with a composite shield is movable by means of a special lifting gear, varying the distance to the reactor core in a range from 10 m to 12 m. Due to this feature, it could be used not only for the reactor monitoring, but also for fundamental research including short-range neutrino oscillations to the sterile state. Supposing one-year mea...

  5. Local coordination state of rare earth in eutectic scintillators for neutron detector applications.

    Science.gov (United States)

    Masai, Hirokazu; Yanagida, Takayuki; Mizoguchi, Teruyasu; Ina, Toshiaki; Miyazaki, Takamichi; Kawaguti, Noriaki; Fukuda, Kentaro

    2015-01-01

    Atomic distribution in phosphors for neutron detection has not been fully elucidated, although their ionization efficiency is strongly dependent on the state of the rare earth in the matrix. In this work, we examine optical properties of Eu-doped 80LiF-20CaF2 eutectics for neutron detector applications based on the Eu distribution. At low concentrations, aggregation of Eu cations is observed, whereas homogeneous atomic dispersion in the CaF2 layer, to substitute Ca(2+) ions, is observed in the eutectics at high concentrations. Eu LIII edge X-ray absorption fine structure (XAFS) analysis suggests that neutron responses do not depend on the amount of Eu(2+) ions. However, transparency, which depends on an ordered lamellar structure, is found to be important for a high light yield in neutron detection. The results confirm the effectiveness of the basic idea concerning the separation of radiation absorbers and activators in particle radiation scintillation and present potential for further improvement of novel bulk detectors. PMID:26292726

  6. Local coordination state of rare earth in eutectic scintillators for neutron detector applications

    Science.gov (United States)

    Masai, Hirokazu; Yanagida, Takayuki; Mizoguchi, Teruyasu; Ina, Toshiaki; Miyazaki, Takamichi; Kawaguti, Noriaki; Fukuda, Kentaro

    2015-08-01

    Atomic distribution in phosphors for neutron detection has not been fully elucidated, although their ionization efficiency is strongly dependent on the state of the rare earth in the matrix. In this work, we examine optical properties of Eu-doped 80LiF-20CaF2 eutectics for neutron detector applications based on the Eu distribution. At low concentrations, aggregation of Eu cations is observed, whereas homogeneous atomic dispersion in the CaF2 layer, to substitute Ca2+ ions, is observed in the eutectics at high concentrations. Eu LIII edge X-ray absorption fine structure (XAFS) analysis suggests that neutron responses do not depend on the amount of Eu2+ ions. However, transparency, which depends on an ordered lamellar structure, is found to be important for a high light yield in neutron detection. The results confirm the effectiveness of the basic idea concerning the separation of radiation absorbers and activators in particle radiation scintillation and present potential for further improvement of novel bulk detectors.

  7. DALI2: A NaI(Tl) detector array for measurements of γ rays from fast nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi, S., E-mail: takesato@riken.jp [RIKEN Nishina Center, Wako, Saitama 351-0198 (Japan); Motobayashi, T. [RIKEN Nishina Center, Wako, Saitama 351-0198 (Japan); Togano, Y. [Department of Physics, Tokyo Institute of Technology, Megro, Tokyo 152-8551 (Japan); Matsushita, M. [CNS, University of Tokyo, RIKEN campus, Wako, Saitama 351-0198 (Japan); Aoi, N. [RCNP, Osaka University, Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Demichi, K.; Hasegawa, H. [Department of Physics, Rikkyo University, Toshima, Tokyo 171-8501 (Japan); Murakami, H. [RIKEN Nishina Center, Wako, Saitama 351-0198 (Japan)

    2014-11-01

    A NaI(Tl) detector array called DALI2 (Detector Array for Low Intensity radiation 2) has been constructed for in-beam γ-ray spectroscopy experiments with fast radioactive isotope (RI) beams. It consists typically of 186 NaI(Tl) scintillators covering polar angles from ∼15° to ∼160° with an average angular resolution of 6° in full width at half maximum. Its high granularity (good angular resolution) enables Doppler-shift corrections that result in, for example, 10% energy resolution and 20% full-energy photopeak efficiency for 1-MeV γ rays emitted from fast-moving nuclei (velocities of v/c≃0.6). DALI2 has been employed successfully in numerous experiments using fast RI beams with velocities of v/c=0.3–0.6 provided by the RIKEN RI Beam Factory.

  8. A readout for large arrays of microwave kinetic inductance detectors.

    Science.gov (United States)

    McHugh, Sean; Mazin, Benjamin A; Serfass, Bruno; Meeker, Seth; O'Brien, Kieran; Duan, Ran; Raffanti, Rick; Werthimer, Dan

    2012-04-01

    Microwave kinetic inductance detectors (MKIDs) are superconducting detectors capable of counting single photons and measuring their energy in the UV, optical, and near-IR. MKIDs feature intrinsic frequency domain multiplexing (FDM) at microwave frequencies, allowing the construction and readout of large arrays. Due to the microwave FDM, MKIDs do not require the complex cryogenic multiplexing electronics used for similar detectors, such as transition edge sensors, but instead transfer this complexity to room temperature electronics where they present a formidable signal processing challenge. In this paper, we describe the first successful effort to build a readout for a photon counting optical/near-IR astronomical instrument, the ARray Camera for Optical to Near-infrared Spectrophotometry. This readout is based on open source hardware developed by the Collaboration for Astronomy Signal Processing and Electronics Research. Designed principally for radio telescope backends, it is flexible enough to be used for a variety of signal processing applications.

  9. Radioactive beam experiments with large gamma-ray detector arrays

    CERN Document Server

    Svensson, C E; Ball, G C; Finlay, P; Garrett, P E; Grinyer, G F; Hackman, G S; Osborne, C J; Sarazin, F; Scraggs, H C; Smith, M B; Waddington, J C

    2003-01-01

    High-resolution gamma-ray spectroscopy is one of the most powerful and versatile experimental techniques in low-energy nuclear physics research. With the continuing development of hyper-pure germanium (HPGe) detector technology, including multi-crystal detectors, contact segmentation, and digital signal processing techniques, large gamma-ray detector arrays will continue to play a major role in the experimental programs at existing and future radioactive ion beam facilities. This paper provides an overview of recent progress in, and future plans for, the development of large gamma-ray spectrometers at such facilities, including the recent commissioning of the 8 pi spectrometer at ISAC-I and the proposed TRIUMF-ISAC gamma-ray escape suppressed spectrometer array for the ISAC-II facility.

  10. Signal Attenuation Curve for Different Surface Detector Arrays

    CERN Document Server

    Vicha, J; Nosek, D; Ebr, J

    2014-01-01

    Modern cosmic ray experiments consisting of large array of particle detectors measure the signals of electromagnetic or muon components or their combination. The correction for an amount of atmosphere passed is applied to the surface detector signal before its conversion to the shower energy. Either Monte Carlo based approach assuming certain composition of primaries or indirect estimation using real data and assuming isotropy of arrival directions can be used. Toy surface arrays of different sensitivities to electromagnetic and muon components are assumed in MC simulations to study effects imposed on attenuation curves for varying composition or possible high energy anisotropy. The possible sensitivity of the attenuation curve to the mass composition is also tested for different array types focusing on a future apparatus that can separate muon and electromagnetic component signals.

  11. Installation and Operation of the SNO Neutral Current Detector Array

    Energy Technology Data Exchange (ETDEWEB)

    Heise, J. [Physics Division, Los Alamos National Laboratory, Los Alamos, NM, 87545 (United States); McGee, S. [Center for Experimental Nuclear Physics and Astrophysics, and Department of Physics, University of Washington, Seattle, WA, 98195 (United States); Rielage, K. [Center for Experimental Nuclear Physics and Astrophysics, and Department of Physics, University of Washington, Seattle, WA, 98195 (United States)

    2005-06-15

    An array of low background detectors designed to capture neutrons liberated by interactions with solar neutrinos was recently installed in the heavy water region of the SNO experiment. The neutral current detector (NCD) array consists of 36 proportional counters filled with {sup 3}He-CF{sub 4} gas and 4 proportional counters filled with {sup 4}He-CF{sub 4}. Special hardware conforming to the high radiopurity requirements in SNO was used to assemble and deploy these counters. Neutron events detected by the NCD array are distinguished from various types of backgrounds on an event-by-event basis using the NCD data acquisition system (NCDDAQ), which employs a mixture of commercial and custom-built electronics equipment. The NCDDAQ is controlled by a custom-built Object-oriented Realtime Control and Acquisition (ORCA) software program, and is fully integrated into the SNO PMT data acquisition system to provide shared trigger information and a combined data stream.

  12. Faraday Rotation (FR) and Interplanetary Scintillation (IPS) Case Studies Using the LOw Frequency ARray (LOFAR)

    Science.gov (United States)

    Bisi, M. M.; Fallows, R. A.; Sobey, C.; Eftekhari, T.; Jensen, E. A.; Jackson, B. V.; Yu, H. S.; Gershman, D. J.; Raines, J. M.; Odstrcil, D.

    2014-12-01

    We present an update on the progress made using the LOw Frequency ARray (LOFAR) next-generation radio telescope for space-weather related activities - namely observations of interplanetary scintillation (IPS) and the first tests of observing heliospheric Faraday rotation (FR). The former has been used for half a century for heliospheric science and much progress has been made in recent years for using IPS in space weather science and forecasting. The latter, typically an astrophysical technique that uses pulsars and extragalactic radio sources to study the Galactic magnetic field, is now being investigated for heliospheric studies. The determination of heliospheric FR, combined with observations of IPS, can provide essential information on the Sun's extended magnetic-field structure out into the inner heliosphere, especially when also combined with other forms of remote-sensing/heliospheric imaging data, and in-situ measurements. Here, we will present recent observations of IPS using LOFAR, including preliminary highlights from the first LOFAR joint IPS and heliospheric FR science campaign and investigate pathways for determining Bzfrom, and an overview of the potential of, such observations. LOFAR is an interferometric phased-array radio telescope that can be used to observe between 10 MHz (depending on ionospheric conditions) and 240 MHz, and consists of many relatively-low-cost antennas. These antennas are organised into 'stations' located in an area of ~100km diameter in the Netherlands, with additional international stations spread across central and western Europe with several more in the planning stages.

  13. A fast, primary-interaction Monte Carlo methodology for determination of total efficiency of cylindrical scintillation gamma-ray detectors

    Directory of Open Access Journals (Sweden)

    Rehman Shakeel U.

    2009-01-01

    Full Text Available A primary-interaction based Monte Carlo algorithm has been developed for determination of the total efficiency of cylindrical scintillation g-ray detectors. This methodology has been implemented in a Matlab based computer program BPIMC. For point isotropic sources at axial locations with respect to the detector axis, excellent agreement has been found between the predictions of the BPIMC code with the corresponding results obtained by using hybrid Monte Carlo as well as by experimental measurements over a wide range of g-ray energy values. For off-axis located point sources, the comparison of the BPIMC predictions with the corresponding results obtained by direct calculations as well as by conventional Monte Carlo schemes shows good agreement validating the proposed algorithm. Using the BPIMC program, the energy dependent detector efficiency has been found to approach an asymptotic profile by increasing either thickness or diameter of scintillator while keeping the other fixed. The variation of energy dependent total efficiency of a 3'x3' NaI(Tl scintillator with axial distance has been studied using the BPIMC code. About two orders of magnitude change in detector efficiency has been observed for zero to 50 cm variation in the axial distance. For small values of axial separation, a similar large variation has also been observed in total efficiency for 137Cs as well as for 60Co sources by increasing the axial-offset from zero to 50 cm.

  14. Use of a large time-compensated scintillation detector in neutron time-of-flight measurements

    Science.gov (United States)

    Goodman, Charles D.

    1979-01-01

    A scintillator for neutron time-of-flight measurements is positioned at a desired angle with respect to the neutron beam, and as a function of the energy thereof, such that the sum of the transit times of the neutrons and photons in the scintillator are substantially independent of the points of scintillations within the scintillator. Extrapolated zero timing is employed rather than the usual constant fraction timing. As a result, a substantially larger scintillator can be employed that substantially increases the data rate and shortens the experiment time.

  15. MEDEA: A multi element detector array for gamma ray and light charged particle detection at the LNS-Catania

    International Nuclear Information System (INIS)

    A 4π highly granular Multi Element Detector Array (MEDEA) for γ-rays and light charged particles is described. Its basic configuration consists of 180 barium fluoride scintillator crystals, arranged in the shape of a ball, plus a forward angle wall of 120 phoswich detectors. The inner radius of the ball (22 cm) and the distance of the wall from the target (55 cm) allow the placement of other detectors in the inner volume. The whole detection system operates under vacuum inside a large scattering chamber. Dedicated electronics has been designed and realized. It includes a powerful hardware second level trigger and preanalysis system, which allows on-line event selection, and a modular VME-bus based data acquisition system. In-beam performances of the system are also described. (orig.)

  16. Development and characterization of a 2D scintillation detector for quality assurance in scanned carbon ion beams

    Science.gov (United States)

    Tamborini, A.; Raffaele, L.; Mirandola, A.; Molinelli, S.; Viviani, C.; Spampinato, S.; Ciocca, M.

    2016-04-01

    At the Centro Nazionale di Adroterapia Oncologica (CNAO Foundation), a two-dimensional high resolution scintillating dosimetry system has been developed and tested for daily Quality Assurance measurements (QA) in carbon ion radiotherapy with active scanning technique, for both single pencil beams and scanned fields produced by a synchrotron accelerator. The detector consists of a thin plane organic scintillator (25×25 cm2, 2 mm thick) coupled with a high spatial resolution CCD camera (0.25 mm) in a light-tight box. A dedicated Labview software was developed for image acquisition triggered with the beam extraction, data post-processing and analysis. The scintillator system was preliminary characterized in terms of short-term reproducibility (found to be within±0.5%), linearity with the number of particles (linear fit χ2 = 0.996) and dependence on particle flux (measured to be < 1.5 %). The detector was then tested for single beam spot measurements (Full Width at Half Maximum and position) and for 6×6 cm2 reference scanned field (determination of homogeneity) for carbon ions with energy from 115 MeV/u up to 400 MeV/u. No major differences in the investigated beam parameters measured with scintillator system and the radiochromic EBT3 reference films were observed. The system allows therefore real-time monitoring of the carbon ion beam relevant parameters, with a significant daily time saving with respect to films currently used. The results of this study show the suitability of the scintillation detector for daily QA in a carbon ion facility with an active beam delivery system.

  17. The NSLS 100 element solid state array detector

    International Nuclear Information System (INIS)

    X-ray absorption studies of dilute samples require fluorescence detection techniques. Since signal-to-noise ratios are governed by the ratio of fluorescent to scattered photons counted by a detector, solid state detectors which can discriminate between fluorescence and scattered photons have become the instruments of choice for trace element measurements. Commercially available 13 element Ge array detectors permitting total count rates < 500 000 counts per second are now in routine use. Since X-ray absorption beamlines at high brightness synchrotron sources can already illuminate most dilute samples with enough flux to saturate the current generation of solid state detectors, the development of next-generation instruments with significantly higher total count rates is essential. We present the design and current status of the 100 elements Si array detector being developed in a collaboration between the NSLS and the Instrumentation Division at Brookhaven National Laboratory. The detecting array consists of a 10 x 10 matrix of 4 mm x 4 mm elements laid out on a single piece of ultrahigh purity silicon mounted at the front end of a liquid nitrogen dewar assembly. A matrix of charge sensitive integrating preamplifiers feed signals to an array of shaping amplifiers, single channel analyzers, and scalers. An electronic switch, delay amplifier, linear gate, digital scope, peak sensing A/D converter, and histogramming memory module provide for complete diagnostics and channel calibration. The entrie instrument is controlled by a LabView 2 application on a MacII ci; the software also provides full control over beamline hardware and performs the data collection. (orig.)

  18. The MINDView brain PET detector, feasibility study based on SiPM arrays

    Science.gov (United States)

    González, Antonio J.; Majewski, Stan; Sánchez, Filomeno; Aussenhofer, Sebastian; Aguilar, Albert; Conde, Pablo; Hernández, Liczandro; Vidal, Luis F.; Pani, Roberto; Bettiol, Marco; Fabbri, Andrea; Bert, Julien; Visvikis, Dimitris; Jackson, Carl; Murphy, John; O'Neill, Kevin; Benlloch, Jose M.

    2016-05-01

    The Multimodal Imaging of Neurological Disorders (MINDView) project aims to develop a dedicated brain Positron Emission Tomography (PET) scanner with sufficient resolution and sensitivity to visualize neurotransmitter pathways and their disruptions in mental disorders for diagnosis and follow-up treatment. The PET system should be compact and fully compatible with a Magnetic Resonance Imaging (MRI) device in order to allow its operation as a PET brain insert in a hybrid imaging setup with most MRI scanners. The proposed design will enable the currently-installed MRI base to be easily upgraded to PET/MRI systems. The current design for the PET insert consists of a 3-ring configuration with 20 modules per ring and an axial field of view of ~15 cm and a geometrical aperture of ~33 cm in diameter. When coupled to the new head Radio Frequency (RF) coil, the inner usable diameter of the complete PET-RF coil insert is reduced to 26 cm. Two scintillator configurations have been tested, namely a 3-layer staggered array of LYSO with 1.5 mm pixel size, with 35×35 elements (6 mm thickness each) and a black-painted monolithic LYSO block also covering about 50×50 mm2 active area with 20 mm thickness. Laboratory test results associated with the current MINDView PET module concept are presented in terms of key parameters' optimization, such as spatial and energy resolution, sensitivity and Depth of Interaction (DOI) capability. It was possible to resolve all pixel elements from the three scintillator layers with energy resolutions as good as 10%. The monolithic scintillator showed average detector resolutions varying from 3.5 mm in the entrance layer to better than 1.5 mm near the photosensor, with average energy resolutions of about 17%.

  19. LENDA, a Low Energy Neutron Detector Array for experiments with radioactive beams in inverse kinematics

    CERN Document Server

    Perdikakis, G; Austin, Sam M; Bazin, D; Caesar, C; Cannon, S; Deaven, J M; Doster, H J; Guess, C J; Hitt, G W; Marks, J; Meharchand, R; Nguyen, D T; Peterman, D; Prinke, A; Scott, M; Shimbara, Y; Thorne, K; Valdez, L; Zegers, R G T

    2011-01-01

    The Low Energy Neutron Detector Array (LENDA) is a neutron time-of-flight (TOF) spectrometer developed at the National Superconducting Cyclotron Lab- oratory (NSCL) for use in inverse kinematics experiments with rare isotope beams. Its design has been motivated by the need to study the spin-isospin response of unstable nuclei using (p, n) charge-exchange reactions at intermediate energies (> 100 MeV/u). It can be used, however, for any reaction study that involves emission of low energy neutrons (150 keV - 10 MeV). The array consists of 24 plastic scintillator bars and is capable of registering the recoiling neutron energy and angle with high detection efficiency. The neutron energy is determined by the time-of-flight technique, while the position of interaction is deduced using the timing and energy information from the two photomultipliers of each bar. A simple test setup utilizing radioactive sources has been used to characterize the array. Results of test measurements are compared with simulations. A neut...

  20. Conference on physics from large γ-ray detector arrays

    International Nuclear Information System (INIS)

    The conference on open-quotes Physics from Large γ-ray Detector Arraysclose quotes is a continuation of the series of conferences that have been organized every two years by the North American Heavy-ion Laboratories. The aim of the conference this year was to encourage discussion of the physics that can be studied with such large arrays. This volume is the collected proceedings from this conference. It discusses properties of nuclear states which can be created in heavy-ion reactions, and which can be observed via such detector systems

  1. Construction and performance of one- and two-dimensional large position-sensitive liquid and plastic scintillation detectors - an application to a neutron polarimeter

    International Nuclear Information System (INIS)

    Large one- and two-dimensional position-sensitive neutron detectors have been developed. Their shapes are a long block and a square and their sizes are 100 x 10 x 7.5 cm3 and 100 x 100 x 10 cm3 for one- and two-dimensional detectors, respectively. Both liquid and plastic scintillators are employed as detector materials. Position resolutions are examined by using monoenergetic neutron beams with energies of 61.6 MeV. The obtained position resolutions in FWHM are 3-5 cm and 4-14 cm for one- and two-dimensional detectors, respectively. Position resolutions are poor near the corner of the two-dimensional detector irrespective of scintillator materials. Scintillation light responses have been compared with predictions of Monte Carlo calculations. Neutron polarimeters at an intermediate energy have been developed by utilizing the position sensitivity of these detectors. (orig.)

  2. Determination of mass attenuation coefficients of some boron ores at 59.54 keV by using scintillation detector

    International Nuclear Information System (INIS)

    The mass attenuation coefficients of the 59.54 keV radiation of 241Am point source in boron ores such as tincal, ulexite and colemanite were determined experimentally by a scintillation detector and theoretically. Since boron ores contain boron, hydrogen, and a lot of elements, they may be used as shielding against neutrons and gammas simultaneously, e.g. for shielding 241Am/Be neutron sources, as they emit both gammas and neutrons.

  3. The TALE Infill Array

    Science.gov (United States)

    Bergman, Douglas

    2009-05-01

    The TALE Infill Array in conjunction with the TALE Tower Detector will provide hybrid coverage of the cosmic ray energy spectrum down to 3x10^16 eV. It will consist of about 100, two square meter scintillators on the surface spaced at 400 m; and 24 buried twelve square meter scintillators. The combination of surface and underground detectors will allow for the determination of the muon content of showers and thus give a handle on cosmic ray composition.

  4. A novel fast-neutron tomography system based on a plastic scintillator array and a compact D-D neutron generator.

    Science.gov (United States)

    Adams, Robert; Zboray, Robert; Prasser, Horst-Michael

    2016-01-01

    Very few experimental imaging studies using a compact neutron generator have been published, and to the knowledge of the authors none have included tomography results using multiple projection angles. Radiography results with a neutron generator, scintillator screen, and camera can be seen in Bogolubov et al. (2005), Cremer et al. (2012), and Li et al. (2014). Comparable results with a position-sensitive photomultiplier tube can be seen in Popov et al. (2011). One study using an array of individual fast neutron detectors in the context of cargo scanning for security purposes is detailed in Eberhardt et al. (2005). In that case, however, the emphasis was on very large objects with a resolution on the order of 1cm, whereas this study focuses on less massive objects and a finer spatial resolution. In Andersson et al. (2014) three fast neutron counters and a D-T generator were used to perform attenuation measurements of test phantoms. Based on the axisymmetry of the test phantoms, the single-projection information was used to calculate radial attenuation distributions of the object, which was compared with the known geometry. In this paper a fast-neutron tomography system based on an array of individual detectors and a purpose-designed compact D-D neutron generator is presented. Each of the 88 detectors consists of a plastic scintillator read out by two Silicon photomultipliers and a dedicated pulse-processing board. Data acquisition for all channels was handled by four single-board microcontrollers. Details of the individual detector design and testing are elaborated upon. Using the complete array, several fast-neutron images of test phantoms were reconstructed, one of which was compared with results using a Co-60 gamma source. The system was shown to be capable of 2mm resolution, with exposure times on the order of several hours per reconstructed tomogram. Details about these measurements and the analysis of the reconstructed images are given, along with a discussion

  5. Heterodyne detection with mismatch correction base on array detector

    Science.gov (United States)

    Hongzhou, Dong; Guoqiang, Li; Ruofu, Yang; Chunping, Yang; Mingwu, Ao

    2016-07-01

    Based on an array detector, a new heterodyne detection system, which can correct the mismatches of amplitude and phase between signal and local oscillation (LO) beams, is presented in this paper. In the light of the fact that, for a heterodyne signal, there is a certain phase difference between the adjacent two samples of analog-to-digital converter (ADC), we propose to correct the spatial phase mismatch by use of the time-domain phase difference. The corrections can be realized by shifting the output sequences acquired from the detector elements in the array, and the steps of the shifting depend on the quantity of spatial phase mismatch. Numerical calculations of heterodyne efficiency are conducted to confirm the excellent performance of our system. Being different from previous works, our system needs not extra optical devices, so it provides probably an effective means to ease the problem resulted from the mismatches.

  6. Heterodyne detection with mismatch correction based on array detector

    Science.gov (United States)

    Dong, Hongzhou; Li, Guoqiang; Yang, Ruofu; Yang, Chunping; Ao, Mingwu

    2016-07-01

    Based on an array detector, a new heterodyne detection system, which can correct the mismatches of amplitude and phase between signal and local oscillation (LO) beams, is presented in this paper. In the light of the fact that, for a heterodyne signal, there is a certain phase difference between the adjacent two samples of analog-to-digital converter (ADC), we propose to correct the spatial phase mismatch by use of the time-domain phase difference. The corrections can be realized by shifting the output sequences acquired from the detector elements in the array, and the steps of the shifting depend on the quantity of spatial phase mismatch. Numerical calculations of heterodyne efficiency are conducted to confirm the excellent performance of our system. Being different from previous works, our system needs not extra optical devices, so it provides probably an effective means to ease the problem resulted from the mismatches.

  7. Fast neutron tomography with real-time pulse-shape discrimination in organic scintillation detectors

    Science.gov (United States)

    Joyce, Malcolm J.; Agar, Stewart; Aspinall, Michael D.; Beaumont, Jonathan S.; Colley, Edmund; Colling, Miriam; Dykes, Joseph; Kardasopoulos, Phoevos; Mitton, Katie

    2016-10-01

    A fast neutron tomography system based on the use of real-time pulse-shape discrimination in 7 organic liquid scintillation detectors is described. The system has been tested with a californium-252 source of dose rate 163 μSv/h at 1 m and neutron emission rate of 1.5×107 per second into 4π and a maximum acquisition time of 2 h, to characterize two 100×100×100 mm3 concrete samples. The first of these was a solid sample and the second has a vertical, cylindrical void. The experimental data, supported by simulations with both Monte Carlo methods and MATLAB®, indicate that the presence of the internal cylindrical void, corners and inhomogeneities in the samples can be discerned. The potential for fast neutron assay of this type with the capability to probe hydrogenous features in large low-Z samples is discussed. Neutron tomography of bulk porous samples is achieved that combines effective penetration not possible with thermal neutrons in the absence of beam hardening.

  8. Neutron and photon spectrometry with liquid scintillation detectors in mixed fields

    CERN Document Server

    Klein, H

    2002-01-01

    Liquid scintillation detectors of type NE213 or BC501A are well suited and routinely used for spectrometry in mixed n-gamma-fields. Neutron- and photon-induced pulse height spectra may be simultaneously recorded making use of the n/gamma-discrimination capability based on pulse shape analysis. The light output functions for the detected secondary charged particles, i.e. electrons, positrons, protons and other charged reaction products, and the pulse height resolution function must carefully be determined. This can be done experimentally, in part via an iterative procedure by comparison with calculations. The response functions can then be reliably calculated by Monte Carlo simulations. Photon response functions calculated with the PHRESP code, which was developed on the basis of the EGS4+PRESTA program package, are in very good agreement with calibrations up to 17 MeV, both in shape and absolute scale. Similarly, neutron response functions calculated with the NRESP7 code well describe the pulse height spectra...

  9. Radiopurity of a CeBr{sub 3} crystal used as scintillation detector

    Energy Technology Data Exchange (ETDEWEB)

    Lutter, Guillaume, E-mail: guillaume.lutter@ec.europa.eu [European Commission, DG JRC, Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, 2440 Geel (Belgium); Hult, Mikael [European Commission, DG JRC, Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, 2440 Geel (Belgium); Billnert, Robert [European Commission, DG JRC, Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, 2440 Geel (Belgium); Fundamental Fysik, Chalmers Tekniska Högskola, 41296 Göteborg (Sweden); Oberstedt, Andreas [Fundamental Fysik, Chalmers Tekniska Högskola, 41296 Göteborg (Sweden); Oberstedt, Stephan; Andreotti, Erica; Marissens, Gerd; Rosengård, Ulf; Tzika, Faidra [European Commission, DG JRC, Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, 2440 Geel (Belgium)

    2013-03-01

    Cerium bromide (CeBr{sub 3}) has recently been shown to exhibit several properties making it a suitable material as a scintillation detector in nuclear physics applications. The intrinsic activity of gamma-ray emitting radionuclides in a 38.1 mm×38.1 mm (diameter×height) crystal of CeBr{sub 3} was investigated. The measurements were carried out in the HADES underground laboratory located 225 m underground. Two primordial radionuclides were detected; {sup 227}Ac (and its daughters) with massic activity of 0.30±0.02 Bq/kg and {sup 138}La with massic activity of 7.4±1.0 mBq/kg. Two activation products were also detected; {sup 139}Ce and {sup 82}Br. Their massic activities (assuming a homogeneous distribution in the crystal) just before taking the CeBr{sub 3} crystal underground were 4.3±0.3 mBq/kg and 18±4 mBq/kg correspondingly. None of the other common primordial radionuclides ({sup 40}K, {sup 226}Ra, {sup 228}Ra, {sup 228}Th, and {sup 235}U) were detected and their detection limits were below 2 mBq/kg except for {sup 238}U for which the upper limit was 135 mBq/kg and {sup 210}Pb with an upper limit of 600 mBq/kg.

  10. Novel discrimination parameters for neutron-gamma discrimination with liquid scintillation detectors using wavelet transform

    International Nuclear Information System (INIS)

    It has been observed that the discrimination performance of the wavelet transform method strongly depends on definition of discrimination parameters. These parameters are usually obtained from a combination of scaling functions at different scales, which represents the energy density of the wavelet coefficients. In this paper, the discrete wavelet transform (DWT) at minimum possible values of scale was investigated. Novel pulse shape discrimination parameters have been proposed for neutron and gamma discrimination in a mixed radiation field and tested with modeled pulses. The performance of these parameters was also validated in terms of quality of discrimination using experimental data of mixed events from an AmBe source collected with BC501 liquid scintillation detector. The quality of discrimination was evaluated by calculating a figure of merit (FOM) with all parameters under same experimental and simulation conditions. The FOM obtained with the proposed novel parameters was also compared with the charge comparison method. The proposed parameters exhibit better FOM as compared to the charge comparison method when high levels of noise are present in the data

  11. SuperTIGER scintillator detector calibration with 30 GeV/nucleon Pb and its fragments

    Science.gov (United States)

    Sasaki, Makoto

    2016-07-01

    The SuperTIGER (Super Trans-Iron Galactic Element Recorder) long-duration balloon instrument has measured the abundances of galactic cosmic-ray elements to provide sensitive tests and clarification of the OB-association model of Galactic cosmic-ray origins. More than 600 nuclei with atomic number Z > 30 were observed on its first flight and the abundances of nuclei have been determined with clear individual element resolution and high statistical precision for 30 CERN with fixed energy 30 GeV/nucleon Pb and its fragments to measure the saturation response of the scintillator detectors, which are essential to determine the abundances of nuclei with atomic number Z > 40. The beamtest results have been used to optimize the Geant4 simulation to represent the flight data, and will be used to interpret the flight data to extend the abundance determination to about _{60}Nd. SuperTIGER was developed by Washington University in St. Louis, NASA Goddard Flight Center, the California Institute of Technology, Jet Propulsion Laboratory, and the University of Minnesota.

  12. A SiPM-based ZnS:$^6$LiF scintillation neutron detector

    CERN Document Server

    Stoykov, A; Greuter, U; Hildebrandt, M; Schlumpf, N

    2014-01-01

    In the work presented here we built and evaluated a single-channel neutron detection unit consisting of a ZnS:$^6$LiF scintillator with embedded WLS fibers readout by a SiPM. The unit has a sensitive volume of 2.4 x 2.8 x 50 mm$^3$; 12 WLS fibers of diameter 0.25 mm are uniformly distributed over this volume and are coupled to a 1 x 1 mm$^2$ active area SiPM. We report the following performance parameters: neutron detection efficiency $\\sim 65\\,$% at $1.2\\,\\AA$, background count rate $< 10^{-3}$ Hz, gamma-sensitivity with $^{60}$Co source $< 10^{-6}$, dead time $\\sim 20\\,\\mu$s, multi-count ratio $< 1\\,$%. All these parameters were achieved up to the SiPM dark count rate of $\\sim 2\\,$MHz. We consider such detection unit as an elementary building block for realization of one-dimensional multichannel detectors for applications in the neutron scattering experimental technique. The dimensions of the unit and the number of embedded fibers can be varied to meet the specific application requirements. The upp...

  13. Extraction of depth-dependent perturbation factors for silicon diodes using a plastic scintillation detector

    Energy Technology Data Exchange (ETDEWEB)

    Lacroix, Frederic; Guillot, Mathieu; McEwen, Malcolm; Gingras, Luc; Beaulieu, Luc [Departement de Radio-Oncologie, Centre hospitalier de l' Universite de Montreal (CHUM), 1560 Sherbrooke est, Montreal, Quebec H2L 4M1, Canada and Departement de Physique, Universite de Montreal, Pavillon Roger-Gaudry (D-428), 2900 Boul. Edouard-Montpetit, Montreal, Quebec H3T 1J4 (Canada); Departement de Physique, de Genie Physique et d' Optique, Universite Laval, Quebec G1K 7P4, Quebec, Canada and Departement de Radio-Oncologie, Hotel-Dieu de Quebec, Centre hospitalier universitaire de Quebec (CHUQ), Quebec, Quebec G1R 2J6 (Canada); Ionizing Radiation Standards, Institute for National Measurement Standards, National Research Council (NRC), Ottawa, Ontario K1A 0R6 (Canada); Departement de Physique, de Genie Physique et d' Optique, Universite Laval, Quebec G1K 7P4, Quebec, Canada and Departement de Radio-Oncologie, Hotel-Dieu de Quebec, Centre hospitalier universitaire de Quebec (CHUQ), Quebec, Quebec G1R 2J6 (Canada)

    2011-10-15

    Purpose: This work presents the experimental extraction of the perturbation factor in megavoltage electron beams for three models of silicon diodes (IBA Dosimetry, EFD and SFD, and the PTW 60012 unshielded) using a plastic scintillation detector (PSD). Methods: The authors used a single scanning PSD mounted on a high-precision scanning tank to measure depth-dose curves in 6-, 12-, and 18-MeV clinical electron beams. They also measured depth-dose curves using the IBA Dosimetry, EFD and SFD, and the PTW 60012 unshielded diodes. The authors used the depth-dose curves measured with the PSD as a perturbation-free reference to extract the perturbation factors of the diodes. Results: The authors found that the perturbation factors for the diodes increased substantially with depth, especially for low-energy electron beams. The experimental results show the same trend as published Monte Carlo simulation results for the EFD diode; however, the perturbations measured experimentally were greater. They found that using an effective point of measurement (EPOM) placed slightly away from the source reduced the variation of perturbation factors with depth and that the optimal EPOM appears to be energy dependent. Conclusions: The manufacturer recommended EPOM appears to be incorrect at low electron energy (6 MeV). In addition, the perturbation factors for diodes may be greater than predicted by Monte Carlo simulations.

  14. An investigation into a suitable scintillator for localising neutron capture within a detector

    OpenAIRE

    Balmer, Matthew; Gamage, Kelum; Taylor, Graeme

    2014-01-01

    Using Monte-Carlo modelling, an investigation into a suitable loaded scintillator for localising neutron capture in a novel neutron survey meter has been undertaken. A comparison of estimated neutron capture location in a scintillator with Geant4 and MCNP simulations was undertaken and a good general agreement between the two models was observed. The interactions of γ emissions from neutron capture in the scintillator are investigated. The results show that the γ emission from neutron capture...

  15. Simulation and Design of Multi-modulars Detector System of Gadolinium-Loaded Liquid Scintillator

    Institute of Scientific and Technical Information of China (English)

    HOU; Long; WANG; Zhao-hui; YU; Guo-liang; WANG; Qi; KANG; Guo-guo; SU; Xiao-bin; ZHANG; Xiao-peng; ZHANG; Kai

    2012-01-01

    <正>The gadolinium-loaded liquid scintillator has the superiority of high detecting efficiency, and it can be used to measure many kinds of nucleus. We improved this technique and construct a 4π liquid scintillator detecting systems which is composed by many liquid scintillators. By coupling with fission chamber, we form a novel research platform which can be used to measure the (n, 2n) and (n, 3n) cross sections of many nuclei.

  16. Active terahertz imaging with Ne indicator lamp detector arrays

    Science.gov (United States)

    Kopeika, N. S.; Abramovich, A.; Yadid-Pecht, O.; Yitzhaky, Y.

    2009-08-01

    The advantages of terahertz (THz) imaging are well known. They penetrate well most non-conducting media and there are no known biological hazards, This makes such imaging systems important for homeland security, as they can be used to image concealed objects and often into rooms or buildings from the outside. There are also biomedical applications that are arising. Unfortunately, THz imaging is quite expensive, especially for real time systems, largely because of the price of the detector. Bolometers and pyroelectric detectors can each easily cost at least hundreds of dollars if not more, thus making focal plane arrays of them quite expensive. We have found that common miniature commercial neon indicator lamps costing typically about 30 cents each exhibit high sensitivity to THz radiation [1-3], with microsecond order rise times, thus making them excellent candidates for such focal plane arrays. NEP is on the order of 10-10 W/Hz1/2. Significant improvement of detection performance is expected when heterodyne detection is used Efforts are being made to develop focal plane array imagers using such devices at 300 GHz. Indeed, preliminary images using 4x4 arrays have already been obtained. An 8x8 VLSI board has been developed and is presently being tested. Since no similar imaging systems have been developed previously, there are many new problems to be solved with such a novel and unconventional imaging system. These devices act as square law detectors, with detected signal proportional to THz power. This allows them to act as mixers in heterodyne detection, thus allowing NEP to be reduced further by almost two orders of magnitude. Plans are to expand the arrays to larger sizes, and to employ super resolution techniques to improve image quality beyond that ordinarily obtainable at THz frequencies.

  17. Imaging MAMA detector systems. [Multi-Anode Microchannel Array

    Science.gov (United States)

    Slater, David C.; Timothy, J. G.; Morgan, Jeffrey S.; Kasle, David B.

    1990-01-01

    Imaging multianode microchannel array (MAMA) detector systems with 1024 x 1024 pixel formats have been produced for visible and UV wavelengths; the UV types employ 'solar blind' photocathodes whose detective quantum efficiencies are significantly higher than those of currently available CCDs operating at far-UV and EUV wavelengths. Attention is presently given to the configurations and performance capabilities of state-of-the-art MAMA detectors, with a view to the development requirements of the hybrid electronic circuits needed for forthcoming spacecraft-sensor applications. Gain, dark noise, uniformity, and dynamic range performance data are presented for the curved-channel 'chevron', 'Z-plate', and helical-channel high gain microchannel plate configurations that are currently under evaluation with MAMA detector systems.

  18. Absolute measurement of anti ν/sub p/ for 252Cf using the ORNL large liquid scintillator neutron detector

    International Nuclear Information System (INIS)

    The ORNL large liquid scintillator detector was used in a precise determination of anti ν/sub p/, the number of neutrons emitted promptly, for spontaneous fission of 252Cf. Measurements of the detector efficiency over a broad energy region were made by means of a proton-recoil technique employing the ORELA white neutron source. Monte Carlo calculation of the detector efficiency for a spectrum representative of 252Cf fission neutrons was calibrated with these elaborate measurements. The unusually flat response of the neutron detector resulted in elimination of several known sources of error. Experimental measurement was coupled with calculational methods to correct for other known errors. These measurements lead to an unusually small estimated uncertainty of 0.2% in the value obtained, anti ν/sub p/ = 3.773 +- 0.007

  19. Digital readouts for large microwave low-temperature detector arrays

    Science.gov (United States)

    Mazin, Benjamin A.; Day, Peter K.; Irwin, Kent D.; Reintsema, Carl D.; Zmuidzinas, Jonas

    2006-04-01

    Over the last several years many different types of low-temperature detectors (LTDs) have been developed that use a microwave resonant circuit as part of their readout. These devices include microwave kinetic inductance detectors (MKID), microwave SQUID readouts for transition edge sensors (TES), and NIS bolometers. Current readout techniques for these devices use analog frequency synthesizers and IQ mixers. While these components are available as microwave integrated circuits, one set is required for each resonator. We are exploring a new readout technique for this class of detectors based on a commercial-off-the-shelf technology called software defined radio (SDR). In this method a fast digital to analog (D/A) converter creates as many tones as desired in the available bandwidth. Our prototype system employs a 100 MS/s 16-bit D/A to generate an arbitrary number of tones in 50 MHz of bandwidth. This signal is then mixed up to the desired detector resonant frequency (˜10 GHz), sent through the detector, then mixed back down to baseband. The baseband signal is then digitized with a series of fast analog to digital converters (80 MS/s, 14-bit). Next, a numerical mixer in a dedicated integrated circuit or FPGA mixes the resonant frequency of a specified detector to 0 Hz, and sends the complex detector output over a computer bus for processing and storage. In this paper we will report on our results in using a prototype system to readout a MKID array, including system noise performance, X-ray pulse response, and cross-talk measurements. We will also discuss how this technique can be scaled to read out many thousands of detectors.

  20. Muon-hadron detector of the carpet-2 array

    Science.gov (United States)

    Dzhappuev, D. D.; Kudzhaev, A. U.; Klimenko, N. F.

    2016-05-01

    The 1-GeV muon-hadron detector of the Carpet-2 multipurpose shower array at the Baksan Neutrino Observatory, Institute for Nuclear Research, Russian Academy of Sciences (INR, Moscow, Russia) is able to record simultaneously muons and hadrons. The procedure developed for this device makes it possible to separate the muon and hadron components to a high degree of precision. The spatial and energy features of the muon and hadron extensive-air-shower components are presented. Experimental data from the Carpet-2 array are contrasted against data from the EAS-TOP and KASCADE arrays and against the results of the calculations based on the CORSIKA (GHEISHA + QGSJET01) code package and performed for primary protons and iron nuclei.

  1. Low background detector with enriched 116CdWO4 crystal scintillators to search for double beta decay of 116Cd

    CERN Document Server

    Barabash, A S; Bernabei, R; Boiko, R S; Cappella, F; Caracciolo, V; Chernyak, D M; Cerulli, R; Danevich, F A; Di Vacri, M L; Dossovitskiy, A E; Galashov, E N; Incicchitti, A; Kobychev, V V; Konovalov, S I; Kovtun, G P; Kudovbenko, V M; Laubenstein, M; Mikhlin, A L; Nisi, S; Poda, D V; Podviyanuk, R B; Polischuk, O G; Shcherban, A P; Shlegel, V N; Solopikhin, D A; Stenin, Yu G; Tretyak, V I; Umatov, V I; Vasiliev, Ya V; Virich, V D

    2011-01-01

    A cadmium tungstate crystal boule enriched in $^{116}$Cd to 82% with mass of 1868 g was grown by the low-thermal-gradient Czochralski technique. The isotopic composition of cadmium and the trace contamination of the crystal were estimated by High Resolution Inductively Coupled Plasma Mass-Spectrometry. The crystal scintillators produced from the boule were subjected to characterization that included measurements of transmittance and energy resolution. A low background scintillation detector with two $^{116}$CdWO$_4$ crystal scintillators (586 g and 589 g) was developed. The detector was running over 1727 h deep underground at the Gran Sasso National Laboratories of the INFN (Italy), which allowed to estimate the radioactive contamination of the enriched crystal scintillators. The radiopurity of a third $^{116}$CdWO$_4$ sample (326 g) was tested with the help of ultra-low background high purity germanium $\\gamma$ detector. Monte Carlo simulations of double $\\beta$ processes in $^{116}$Cd were used to estimate ...

  2. Mechanical design and development of TES bolometer detector arrays for the Advanced ACTPol experiment

    CERN Document Server

    Ward, Jonathan T; Beall, James A; Choi, Steve K; Crowley, Kevin T; Devlin, Mark J; Duff, Shannon M; Gallardo, Patricio M; Henderson, Shawn W; Ho, Shuay-Pwu Patty; Hilton, Gene; Hubmayr, Johannes; Khavari, Niloufar; Klein, Jeffrey; Koopman, Brian J; Li, Dale; McMahon, Jeffrey; Mumby, Grace; Nati, Federico; Niemack, Michael D; Page, Lyman A; Salatino, Maria; Schillaci, Alessandro; Schmitt, Benjamin L; Simon, Sara M; Staggs, Suzanne T; Thornton, Robert; Ullom, Joel N; Vavagiakis, Eve M; Wollack, Edward J

    2016-01-01

    The next generation Advanced ACTPol (AdvACT) experiment is currently underway and will consist of four Transition Edge Sensor (TES) bolometer arrays, with three operating together, totaling ~5800 detectors on the sky. Building on experience gained with the ACTPol detector arrays, AdvACT will utilize various new technologies, including 150mm detector wafers equipped with multichroic pixels, allowing for a more densely packed focal plane. Each set of detectors includes a feedhorn array of stacked silicon wafers which form a spline profile leading to each pixel. This is then followed by a waveguide interface plate, detector wafer, back short cavity plate, and backshort cap. Each array is housed in a custom designed structure manufactured from high purity copper and then gold plated. In addition to the detector array assembly, the array package also encloses cryogenic readout electronics. We present the full mechanical design of the AdvACT high frequency (HF) detector array package along with a detailed look at t...

  3. A new detector array for charged particle spectroscopy

    CERN Document Server

    Cowin, R L; Chappell, S P G; Clarke, N M; Freer, M; Fulton, B R; Cunningham, R A; Curtis, N; Dillon, G; Lilley, J; Jones, C D; Lee, P; Rae, W D M

    1999-01-01

    A compact and highly segmented detector array consisting of 44 gas-silicon-caesium iodide, position sensitive, particle identification detector telescopes and up to 10 position-sensitive, silicon strip detectors has been constructed for the study of light-ion-heavy-ion reactions including cluster break-up in the energy range 5-15 MeV/nucleon. The detectors are housed in a purpose built vacuum chamber. The telescopes are placed in fixed positions, covering the forward hemisphere from 3 to 30 deg. in the laboratory with the target placed at 535 mm from the front of the telescopes or 6-52 deg. with the target placed at 215 mm. The strip detectors are placed in any of 30 fixed positions in the forward hemisphere. For 85 MeV sup 1 sup 2 C ions the telescope energy resolution (gas plus silicon) is 345 keV with an angular resolution of 0.03 deg. . Using the gas-silicon section ions with Z up to 21 can be identified. For ions that pass through the silicon isotopic identification is achieved using the silicon-CsI comb...

  4. Test of digital neutron–gamma discrimination with four different photomultiplier tubes for the NEutron Detector Array (NEDA)

    International Nuclear Information System (INIS)

    A comparative study of the neutron–γ discrimination performance of a liquid scintillator detector BC501A coupled to four different 5 in. photomultiplier tubes (ET9390kb, R11833-100, XP4512 and R4144) was carried out. Both the Charge Comparison method and the Integrated Rise-Time method were implemented digitally to discriminate between neutrons and γ rays emitted by a 252Cf source. In both methods, the neutron–γ discrimination capabilities of the four photomultiplier tubes were quantitatively compared by evaluating their figure-of-merit values at different energy regions between 50 keVee and 1000 keVee. Additionally, the results were further verified qualitatively using time-of-flight to distinguish γ rays and neutrons. The results consistently show that photomultiplier tubes R11833-100 and ET9390kb generally perform best regarding neutron–γ discrimination with only slight differences in figure-of-merit values. This superiority can be explained by their relatively higher photoelectron yield, which indicates that a scintillator detector coupled to a photomultiplier tube with higher photoelectron yield tends to result in better neutron–γ discrimination performance. The results of this work will provide reference for the choice of photomultiplier tubes for future neutron detector arrays like NEDA

  5. Test of digital neutron–gamma discrimination with four different photomultiplier tubes for the NEutron Detector Array (NEDA)

    Energy Technology Data Exchange (ETDEWEB)

    Luo, X.L., E-mail: luo.xiaoliang@physics.uu.se [Department of Instrument Science and Technology, College of Mechatronics and Automation, National University of Defense Technology, Changsha (China); Department of Physics and Astronomy, Uppsala University, SE-75120 Uppsala (Sweden); Modamio, V. [INFN, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Padova (Italy); Nyberg, J. [Department of Physics and Astronomy, Uppsala University, SE-75120 Uppsala (Sweden); Valiente-Dobón, J.J. [INFN, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Padova (Italy); Nishada, Q. [Department of Physics and Astronomy, Uppsala University, SE-75120 Uppsala (Sweden); Angelis, G. de [INFN, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Padova (Italy); Agramunt, J. [IFIC-CSIC, University of Valencia, Valencia (Spain); Egea, F.J. [IFIC-CSIC, University of Valencia, Valencia (Spain); Faculty of Engineering and Natural Sciences, Istanbul Sabahattin Zaim University, Istanbul (Turkey); Erduran, M.N.; Ertürk, S. [Nigde Universitesi, Fen-Edebiyat Falkültesi, Fizik Bölümü, Nigde (Turkey); France, G. de [GANIL, CEA/DSAM and CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 05 (France); Gadea, A. [IFIC-CSIC, University of Valencia, Valencia (Spain); González, V. [Department of Electronic Engineering, University of Valencia, E-46071 Valencia (Spain); Hüyük, T. [IFIC-CSIC, University of Valencia, Valencia (Spain); Jaworski, G. [Faculty of Physics, Warsaw University of Technology, ul. Koszykowa 75, 00-662 Warszawa (Poland); Heavy Ion Laboratory, University of Warsaw, ul. Pasteura 5A, 02-093 Warszawa (Poland); Moszyński, M. [Heavy Ion Laboratory, University of Warsaw, ul. Pasteura 5A, 02-093 Warszawa (Poland); National Centre for Nuclear Research, A. Soltana 7, PL 05-400 Otwock-Swierk (Poland); and others

    2014-12-11

    A comparative study of the neutron–γ discrimination performance of a liquid scintillator detector BC501A coupled to four different 5 in. photomultiplier tubes (ET9390kb, R11833-100, XP4512 and R4144) was carried out. Both the Charge Comparison method and the Integrated Rise-Time method were implemented digitally to discriminate between neutrons and γ rays emitted by a {sup 252}Cf source. In both methods, the neutron–γ discrimination capabilities of the four photomultiplier tubes were quantitatively compared by evaluating their figure-of-merit values at different energy regions between 50 keVee and 1000 keVee. Additionally, the results were further verified qualitatively using time-of-flight to distinguish γ rays and neutrons. The results consistently show that photomultiplier tubes R11833-100 and ET9390kb generally perform best regarding neutron–γ discrimination with only slight differences in figure-of-merit values. This superiority can be explained by their relatively higher photoelectron yield, which indicates that a scintillator detector coupled to a photomultiplier tube with higher photoelectron yield tends to result in better neutron–γ discrimination performance. The results of this work will provide reference for the choice of photomultiplier tubes for future neutron detector arrays like NEDA.

  6. Timing resolution improvement using DOI information in a four-layer scintillation detector for TOF-PET

    Energy Technology Data Exchange (ETDEWEB)

    Shibuya, Kengo [jPET Project Team, Molecular Imaging Center, National Institute of Radiological Sciences, Anagawa 4-9-1, Inage-ku, Chiba 263-0024 (Japan)], E-mail: shibuken@gakushikai.jp; Nishikido, Fumihiko [jPET Project Team, Molecular Imaging Center, National Institute of Radiological Sciences, Anagawa 4-9-1, Inage-ku, Chiba 263-0024 (Japan); Tsuda, Tomoaki [Technology Research Laboratory, Shimadzu Corporation, Hikaridai 3-9-4, Seika-cho, Kyoto 619-0237 (Japan); Kobayashi, Tetsuya [Department of Medical System Engineering, Graduate School of Engineering, Chiba University, Yayoi 1-33, Inage-ku, Chiba 263-8522 (Japan); Lam, Chihfung; Yamaya, Taiga; Yoshida, Eiji; Inadama, Naoko; Murayama, Hideo [jPET Project Team, Molecular Imaging Center, National Institute of Radiological Sciences, Anagawa 4-9-1, Inage-ku, Chiba 263-0024 (Japan)

    2008-08-11

    Depth-of-interaction (DOI) detectors are considered to be advantageous for time-of-flight positron emission tomography (TOF-PET) because they can correct timing errors arising in the scintillation crystals due to a propagation speed difference between annihilation radiation and scintillation photons. We experimentally measured this timing error, using our four-layer DOI encoding method. The upper layers exhibited the larger timing delays due to the longer path lengths after conversion from annihilation radiation into scintillation photons that traveled by zigzag paths at a speed decreased by a factor of the refractive index (n). The maximum timing delay between the uppermost and the lowermost layers was evaluated as 164 ps when n=1.47. A TOF error correction was demonstrated to improve the timing resolution of the four-layer DOI detector by 10.3%, which would increase the effective sensitivity of the scanner by about 12% comparison with a non-DOI TOF-PET scanner. This is the first step towards combining these two important fields in PET instrumentation, namely DOI and TOF, for the purpose of achieving a higher sensitivity as well as a more uniform spatial resolution.

  7. A large acceptance scintillator detector with wavelength shifting fibre read-out for search of eta-nucleus bound states

    CERN Document Server

    Kilian, K; Kirillov, Da; Kirillov, Di; Kolev, D; Kravcikova, M; Kutsarova, T; Lesiak, M; Lieb, J; Machner, H; Magiera, A; Maier, R; Martinská, G; Nedev, S; Piskunov, N; Prasuhn, D; Prottic, D; Ritman, J; Von Rossen, P; Roy, B J; Shukla, P; Sitnik, I; Siudak, R; Tsenov, R; Ulicny, M; Urbán, J; Vankova, G

    2007-01-01

    A large acceptance scintillator detector with wavelength shifting optical fibre readout has been designed and built to detect the decay particles of $\\eta$-nucleus bound system (the so-called $\\eta$-mesic nuclei), namely, protons and pions. The detector, named as ENSTAR detector, consists of 122 pieces of plastic scintillator of various shapes and sizes, which are arranged in a cylindrical geometry to provide particle identification, energy loss and coarse position information for these particles. A solid angle coverage of $\\sim$95% of total 4$\\pi$ is obtained in the present design of the detector. Monte Carlo phase space calculations performed to simulate the formation and decay of $\\eta$-mesic nuclei suggest that its decay particles, the protons and pions are emitted with an opening angle of 150$^\\circ \\pm 20^\\circ$, and with energies in the range of 25 to 300 MeV and 225 to 450 MeV respectively. The detailed GEANT simulations show that $\\sim$ 80 % of the decay particles (protons and pions) can be detected ...

  8. Digital pulse-timing technique for the neutron detector array NEDA

    International Nuclear Information System (INIS)

    A new digital pulse-timing algorithm, to be used with the future neutron detector array NEDA, has been developed and tested. The time resolution of four 5 in. diameter photomultiplier tubes (XP4512, R4144, R11833-100, and ET9390-kb), coupled to a cylindrical 5 in. by 5 in. BC501A liquid scintillator detector was measured by employing digital sampling electronics and a constant fraction discriminator (CFD) algorithm. The zero crossing of the CFD algorithm was obtained with a cubic spline interpolation, which was continuous up to the second derivative. The performance of the algorithm was studied at sampling rates of 500 MS/s and 200 MS/s. The time resolution obtained with the digital electronics was compared to the values acquired with a standard analog CFD. The result of this comparison shows that the time resolution from the analog and the digital measurements at 500 MS/s and at 200 MS/s are within 15% for all the tested photomultiplier tubes

  9. Validating plastic scintillation detectors for photon dosimetry in the radiologic energy range

    Energy Technology Data Exchange (ETDEWEB)

    Lessard, Francois; Archambault, Louis; Plamondon, Mathieu [Departement de physique, de genie physique et d' optique, Universite Laval, Quebec, Quebec G1K 7P4, Canada and Departement de radio-oncologie, Hotel-Dieu de Quebec, Centre hospitalier universitaire de Quebec, Quebec G1R 2J6 (Canada); Departement de physique, de genie physique et d' optique, Universite Laval, Quebec, Quebec G1K 7P4 (Canada); Departement de radio-oncologie, Hotel-Dieu de Quebec, Centre hospitalier universitaire de Quebec, Quebec G1R 2J6 (Canada) and Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Departement de physique, de genie physique et d' optique, Universite Laval, Quebec, Quebec G1K 7P4, Canada and Departement de radio-oncologie, Hotel-Dieu de Quebec, Centre hospitalier universitaire de Quebec, Quebec G1R 2J6 (Canada); and others

    2012-09-15

    Purpose: Photon dosimetry in the kilovolt (kV) energy range represents a major challenge for diagnostic and interventional radiology and superficial therapy. Plastic scintillation detectors (PSDs) are potentially good candidates for this task. This study proposes a simple way to obtain accurate correction factors to compensate for the response of PSDs to photon energies between 80 and 150 kVp. The performance of PSDs is also investigated to determine their potential usefulness in the diagnostic energy range. Methods: A 1-mm-diameter, 10-mm-long PSD was irradiated by a Therapax SXT 150 unit using five different beam qualities made of tube potentials ranging from 80 to 150 kVp and filtration thickness ranging from 0.8 to 0.2 mmAl + 1.0 mmCu. The light emitted by the detector was collected using an 8-m-long optical fiber and a polychromatic photodiode, which converted the scintillation photons to an electrical current. The PSD response was compared with the reference free air dose rate measured with a calibrated Farmer NE2571 ionization chamber. PSD measurements were corrected using spectra-weighted corrections, accounting for mass energy-absorption coefficient differences between the sensitive volumes of the ionization chamber and the PSD, as suggested by large cavity theory (LCT). Beam spectra were obtained from x-ray simulation software and validated experimentally using a CdTe spectrometer. Correction factors were also obtained using Monte Carlo (MC) simulations. Percent depth dose (PDD) measurements were compensated for beam hardening using the LCT correction method. These PDD measurements were compared with uncorrected PSD data, PDD measurements obtained using Gafchromic films, Monte Carlo simulations, and previous data. Results: For each beam quality used, the authors observed an increase of the energy response with effective energy when no correction was applied to the PSD response. Using the LCT correction, the PSD response was almost energy independent, with

  10. Fast, High-Precision Readout Circuit for Detector Arrays

    Science.gov (United States)

    Rider, David M.; Hancock, Bruce R.; Key, Richard W.; Cunningham, Thomas J.; Wrigley, Chris J.; Seshadri, Suresh; Sander, Stanley P.; Blavier, Jean-Francois L.

    2013-01-01

    The GEO-CAPE mission described in NASA's Earth Science and Applications Decadal Survey requires high spatial, temporal, and spectral resolution measurements to monitor and characterize the rapidly changing chemistry of the troposphere over North and South Americas. High-frame-rate focal plane arrays (FPAs) with many pixels are needed to enable such measurements. A high-throughput digital detector readout integrated circuit (ROIC) that meets the GEO-CAPE FPA needs has been developed, fabricated, and tested. The ROIC is based on an innovative charge integrating, fast, high-precision analog-to-digital circuit that is built into each pixel. The 128×128-pixel ROIC digitizes all 16,384 pixels simultaneously at frame rates up to 16 kHz to provide a completely digital output on a single integrated circuit at an unprecedented rate of 262 million pixels per second. The approach eliminates the need for off focal plane electronics, greatly reducing volume, mass, and power compared to conventional FPA implementations. A focal plane based on this ROIC will require less than 2 W of power on a 1×1-cm integrated circuit. The ROIC is fabricated of silicon using CMOS technology. It is designed to be indium bump bonded to a variety of detector materials including silicon PIN diodes, indium antimonide (InSb), indium gallium arsenide (In- GaAs), and mercury cadmium telluride (HgCdTe) detector arrays to provide coverage over a broad spectral range in the infrared, visible, and ultraviolet spectral ranges.

  11. Standard practice for radiological examination using digital detector arrays

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This practice establishes the minimum requirements for radiological examination for metallic and nonmetallic material using a digital detector array (DDA) system. 1.2 The requirements in this practice are intended to control the quality of radiologic images and are not intended to establish acceptance criteria for parts or materials. 1.3 This practice covers the radiologic examination with DDAs including DDAs described in Practice E2597 such as a device that contains a photoconductor attached to a Thin Film Transistor (TFT) read out structure, a device that has a phosphor coupled directly to an amorphous silicon read-out structure, and devices where a phosphor is coupled to a CMOS (Complementary metal–oxide–semiconductor) array, a Linear Detector Array (LDA) or a CCD (charge coupled device) crystalline silicon read-out structure. 1.4 The DDA shall be selected for an NDT application based on knowledge of the technology described in Guide , and of the selected DDA properties provided by the manufactu...

  12. Topological detector: measuring continuous dosimetric quantities with few-element detector array

    Science.gov (United States)

    Han, Zhaohui; Brivio, Davide; Sajo, Erno; Zygmanski, Piotr

    2016-08-01

    A prototype topological detector was fabricated and investigated for quality assurance of radiation producing medical devices. Unlike a typical array or flat panel detector, a topological detector, while capable of achieving a very high spatial resolution, consists of only a few elements and therefore is much simpler in construction and more cost effective. The key feature allowing this advancement is a geometry-driven design that is customized for a specific dosimetric application. In the current work, a topological detector of two elements was examined for the positioning verification of the radiation collimating devices (jaws, MLCs, and blades etc). The detector was diagonally segmented from a rectangular thin film strip (2.5 cm  ×  15 cm), giving two contiguous but independent detector elements. The segmented area was the central portion of the strip measuring 5 cm in length. Under irradiation, signals from each detector element were separately digitized using a commercial multichannel data acquisition system. The center and size of an x-ray field, which were uniquely determined by the collimator positions, were shown mathematically to relate to the difference and sum of the two signals. As a proof of concept, experiments were carried out using slit x-ray fields ranging from 2 mm to 20 mm in size. It was demonstrated that, the collimator positions can be accurately measured with sub-millimeter precisions.

  13. Scintillating glass, fiber-optic plate detectors for active target and tracking applications in high energy physics experiments

    International Nuclear Information System (INIS)

    The authors have studied the performance of scintillating glass fiber-optic plates using 10 GeV/c particles at the SLAC test beam. The plates were composed of: Terbium activated cladded-glass cores in a matrix of 15 μm spacing; and Cerium activated cladded-glass cores in a matrix of variable spacing 6-10 μm. The target plates were viewed with a three-stage, gatable image intensifier. Particle tracks and nuclear interactions were recorded on film for both materials. We observe 5 detected hits/mm for minimum ionizing particles for the Tb glass, and 1-2 hits/mm for the Ce glass. The test results indicate that scintillating glass fiber-optic plates can be used as high spatial resolution tracking detectors for both fixed target and colliding beam experiments

  14. Novel Multiplexing Technique for Detector and Mixer Arrays

    Science.gov (United States)

    Karasik, Boris S.; McGrath, William R.

    2001-01-01

    Future submillimeter and far-infrared space telescopes will require large-format (many 1000's of elements) imaging detector arrays to perform state-of-the-art astronomical observations. A crucial issue related to a focal plane array is a readout scheme which is compatible with large numbers of cryogenically-cooled (typically < 1 K) detectors elements. When the number of elements becomes of the order of thousands, the physical layout for individual readout amplifiers becomes nearly impossible to realize for practical systems. Another important concern is the large number of wires leading to a 0.1-0.3 K platform. In the case of superconducting transition edge sensors (TES), a scheme for time-division multiplexing of SQUID read-out amplifiers has been recently demonstrated. In this scheme the number of SQUIDs is equal to the number (N) of the detectors, but only one SQUID is turned on at a time. The SQUIDs are connected in series in each column of the array, so the number of wires leading to the amplifiers can be reduced, but it is still of the order of N. Another approach uses a frequency domain multiplexing scheme of the bolometer array. The bolometers are biased with ac currents whose frequencies are individual for each element and are much higher than the bolometer bandwidth. The output signals are connected in series in a summing loop which is coupled to a single SQUID amplifier. The total number of channels depends on the ratio between the SQUID bandwidth and the bolometer bandwidth and can be at least 100 according to the authors. An important concern about this technique is a contribution of the out-of-band Johnson noise which multiplies by factor N(exp 1/2) for each frequency channel. We propose a novel solution for large format arrays based on the Hadamard transform coding technique which requires only one amplifier to read out the entire array of potentially many 1000's of elements and uses approximately 10 wires between the cold stage and room temperature

  15. Optical simulations of a liquid scintillator detector for reactor neutrino experiments

    Energy Technology Data Exchange (ETDEWEB)

    Orebi Gann, Gabriel, E-mail: g.orebi-gann1@physics.ox.ac.uk [Department of Physics, University of Oxford, Oxford, OX1 3RH (United Kingdom); Seibert, Stanley, E-mail: volsung@physics.utexas.edu [Department of Physics, University of Texas at Austin, Austin, TX 78712 (United States); Tunnell, Christopher, E-mail: tunnell@mail.utexas.edu [Department of Physics, University of Texas at Austin, Austin, TX 78712 (United States)

    2011-12-15

    Described below are simulations of certain optical properties of a spherical liquid scintillator reactor neutrino experiment. Considered are the addition of concentrators to the photomultiplier tubes (PMTs) and an LED calibration system.

  16. An MLC calibration method using a detector array

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Thomas A.; Kahler, Darren; Simon, William E.; Fox, Christopher; Li, Jonathan; Palta, Jatinder; Liu, Chihray [Department of Nuclear and Radiological Engineering, University of Florida, 202 Nuclear Science Building, Gainesville, Florida 32611-8300 (United States); Sun Nuclear Corporation, 425-A Pineda Court, Melbourne, Florida 32940 (United States) and Department of Radiation Oncology, Health Science Center, University of Florida, P.O. Box 100385, Gainesville, Florida 32610-0385 (United States); Department of Radiation Oncology, Health Science Center, University of Florida, P.O. Box 100385, Gainesville, Florida 32610-0385 (United States); Sun Nuclear Corporation, 425-A Pineda Court, Melbourne, Florida 32940 (United States); Department of Radiation Oncology, Tulane University, 1415 Tulane Ave, HC65, New Orleans, Louisiana 70112 (United States); Department of Radiation Oncology, Health Science Center, University of Florida, P.O. Box 100385, Gainesville, Florida 32610-0385 (United States)

    2009-10-15

    Purpose: The authors have developed a quantitative calibration method for a multileaf collimator (MLC) which measures individual leaf positions relative to the MLC backup jaw on an Elekta Synergy linear accelerator. Methods: The method utilizes a commercially available two-axis detector array (Profiler 2; Sun Nuclear Corporation, Melbourne, FL). To calibrate the MLC bank, its backup jaw is positioned at the central axis and the opposing jaw is retracted to create a half-beam configuration. The position of the backup jaws field edge is then measured with the array to obtain what is termed the radiation defined reference line. The positions of the individual leaf ends relative to this reference line are then inferred by the detector response in the leaf end penumbra. Iteratively adjusting and remeasuring the leaf end positions to within specifications completes the calibration. Using the backup jaw as a reference for the leaf end positions is based on three assumptions: (1) The leading edge of an MLC leaf bank is parallel to its backup jaw's leading edge, (2) the backup jaw position is reproducible, and (3) the measured radiation field edge created by each leaf end is representative of that leaf's position. Data from an electronic portal imaging device (EPID) were used in a similar analysis to check the results obtained with the array. Results: The relative leaf end positions measured with the array differed from those measured with the EPID by an average of 0.11 {+-}0.09 mm per leaf. The maximum leaf positional change measured with the Profiler 2 over a 3 month period was 0.51 mm. A leaf positional accuracy of {+-}0.4 mm is easily attainable through the iterative calibration process. The method requires an average of 40 min to measure both leaf banks. Conclusions: This work demonstrates that the Profiler 2 is an effective tool for efficient and quantitative MLC quality assurance and calibration.

  17. Proposal for research and development on a central tracking detector based on scintillating fibres

    CERN Document Server

    D'Ambrosio, C; Leutz, H; Piedigrossi, D; Seidl, W; Tailhardat, S; Taufer, M; Güsten, H; Destruel, P; Puertolas, D; Gensch, Ulrich; Schlenstedt, S; CERN. Geneva. Detector Research and Development Committee

    1990-01-01

    Among the techniques envisaged to realize particle tracking at the LHC, scintillating fibres form a reasonable compromise in terms of price, hit density, space resolution, response time, occupancy and heat production. This proposal covers the current status and achievements of the scintillating fibre technique and presents a future R&D programme at CERN, with reference in particular to the improvement of hit density for small diameter fibres and to the further development of an optoelectronic delay line for track image readout.

  18. Impact of the Fano Factor on Position and Energy Estimation in Scintillation Detectors

    OpenAIRE

    Bora, Vaibhav; Barrett, Harrison H.; Jha, Abhinav K.; Clarkson, Eric

    2015-01-01

    The Fano factor for an integer-valued random variable is defined as the ratio of its variance to its mean. Light from various scintillation crystals have been reported to have Fano factors from sub-Poisson (Fano factor 1). For a given mean, a smaller Fano factor implies a smaller variance and thus less noise. We investigated if lower noise in the scintillation light will result in better spatial and energy resolutions. The impact of Fano factor on the esti...

  19. The light-yield response of a NE-213 liquid-scintillator detector measured using 2 -- 6 MeV tagged neutrons

    CERN Document Server

    Scherzinger, J; Annand, J R M; Fissum, K G; Hall-Wilton, R; Kanaki, K; Lundin, M; Nilsson, B; Perrey, H; Rosborg, A; Svensson, H

    2016-01-01

    The response of a NE-213 liquid-scintillator detector has been measured using tagged neutrons from 2--6 MeV originating from an Am/Be neutron source. The neutron energies were determined using the time-of-flight technique. Pulse-shape discrimination was employed to discern between gamma-rays and neutrons. The behavior of both the fast (35 ns) and the combined fast and slow (475 ns) components of the neutron scintillation-light pulses were studied. Three different prescriptions were used to relate the neutron maximum energy-transfer edges to the corresponding recoil-proton scintillation-light yields, and the results were compared to simulations. Parametrizations which predict the fast or total light yield of the scintillation pulses were also tested. Our results agree with both existing data and existing parametrizations. We observe a clear sensitivity to the portion and length of the neutron scintillation-light pulse considered.

  20. Study of digital pulse shape discrimination method for n-{\\gamma} separation of EJ-301 liquid scintillation detector

    CERN Document Server

    Wan, Bo; Chen, Liang; Ge, Honglin; Ma, Fei; Zhang, Hongbin; Ju, Yongqin; Zhang, Yanbin; Li, Yanyan; Xu, Xiaowei

    2015-01-01

    A digital pulse shape discrimination system based on a programmable module NI-5772 has been established and tested with EJ-301 liquid scintillation detector. The module was operated by means of running programs developed in LabVIEW with the sampling frequency up to 1.6GS/s. Standard gamma sources 22Na, 137Cs and 60Co were used to calibrate the EJ-301 liquid scintillation detector, and the gamma response function has been obtained. Digital algorithms for charge comparison method and zero-crossing method have been developed. The experimental results showed that both digital signal processing (DSP) algorithms could discriminate neutrons from gamma-rays. Moreover, the zero-crossing method shows better n-{\\gamma} discrimination at 80 keVee and lower, whereas the charge comparison method gives better results at higher thresholds. In addition, the figure-of-merit (FOM) of two different dimension detectors were extracted at 9 energy thresholds, and it was found that the smaller one presented a better n-{\\gamma} separ...

  1. Analysis of the scintillation mechanism in a pressurized 4He fast neutron detector using pulse shape fitting

    Directory of Open Access Journals (Sweden)

    R.P. Kelley

    2015-03-01

    Full Text Available An empirical investigation of the scintillation mechanism in a pressurized 4He gas fast neutron detector was conducted using pulse shape fitting. Scintillation signals from neutron interactions were measured and averaged to produce a single generic neutron pulse shape from both a 252Cf spontaneous fission source and a (d,d neutron generator. An expression for light output over time was then developed by treating the decay of helium excited states in the same manner as the decay of radioactive isotopes. This pulse shape expression was fitted to the measured neutron pulse shape using a least-squares optimization algorithm, allowing an empirical analysis of the mechanism of scintillation inside the 4He detector. A further understanding of this mechanism in the 4He detector will advance the use of this system as a neutron spectrometer. For 252Cf neutrons, the triplet and singlet time constants were found to be 970 ns and 686 ns, respectively. For neutrons from the (d,d generator, the time constants were found to be 884 ns and 636 ns. Differences were noted in the magnitude of these parameters compared to previously published data, however the general relationships were noted to be the same and checked with expected trends from theory. Of the excited helium states produced from a 252Cf neutron interaction, 76% were found to be born as triplet states, similar to the result from the neutron generator of 71%. The two sources yielded similar pulse shapes despite having very different neutron energy spectra, validating the robustness of the fits across various neutron energies.

  2. Analysis of the scintillation mechanism in a pressurized 4He fast neutron detector using pulse shape fitting

    International Nuclear Information System (INIS)

    An empirical investigation of the scintillation mechanism in a pressurized 4He gas fast neutron detector was conducted using pulse shape fitting. Scintillation signals from neutron interactions were measured and averaged to produce a single generic neutron pulse shape from both a 252Cf spontaneous fission source and a (d,d) neutron generator. An expression for light output over time was then developed by treating the decay of helium excited states in the same manner as the decay of radioactive isotopes. This pulse shape expression was fitted to the measured neutron pulse shape using a least-squares optimization algorithm, allowing an empirical analysis of the mechanism of scintillation inside the 4He detector. A further understanding of this mechanism in the 4He detector will advance the use of this system as a neutron spectrometer. For 252Cf neutrons, the triplet and singlet time constants were found to be 970 ns and 686 ns, respectively. For neutrons from the (d,d) generator, the time constants were found to be 884 ns and 636 ns. Differences were noted in the magnitude of these parameters compared to previously published data, however the general relationships were noted to be the same and checked with expected trends from theory. Of the excited helium states produced from a 252Cf neutron interaction, 76% were found to be born as triplet states, similar to the result from the neutron generator of 71%. The two sources yielded similar pulse shapes despite having very different neutron energy spectra, validating the robustness of the fits across various neutron energies

  3. LHCb Upgrade: Scintillating Fibre Tracker

    Science.gov (United States)

    Tobin, Mark

    2016-07-01

    The LHCb detector will be upgraded during the Long Shutdown 2 (LS2) of the LHC in order to cope with higher instantaneous luminosities and to read out the data at 40 MHz using a trigger-less read-out system. All front-end electronics will be replaced and several sub-detectors must be redesigned to cope with higher occupancy. The current tracking detectors downstream of the LHCb dipole magnet will be replaced by the Scintillating Fibre (SciFi) Tracker. The SciFi Tracker will use scintillating fibres read out by Silicon Photomultipliers (SiPMs). State-of-the-art multi-channel SiPM arrays are being developed to read out the fibres and a custom ASIC will be used to digitise the signals from the SiPMs. The evolution of the design since the Technical Design Report in 2014 and the latest R & D results are presented.

  4. Results of low energy background measurements with the Liquid Scintillation Detector (LSD) of the Mont Blanc Laboratory

    Science.gov (United States)

    Aglietta, M.; Badino, G.; Bologna, G. F.; Castagnoli, C.; Fulgione, W.; Galeotti, P.; Saavedra, O.; Trinchero, G. C.; Vernetto, S.; Dadykin, V. L.

    1985-01-01

    The 90 tons liquid scintillation detector (LSD) is fully running since October 1984, at a depth of 5,200 hg/sq cm of standard rock underground. The main goal is to search for neutrino bursts from collapsing stars. The experiment is very sensitive to detect low energy particles and has a very good signature to gamma-rays from (n,p) reaction which follows the upsilon e + p yields n + e sup + neutrino capture. The analysis of data is presented and the preliminary results on low energy measurements are discussed.

  5. Liquid scintillators and liquefied rare gases for particle detectors. Background-determination in Double Chooz and scintillation properties of liquid argon

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, Martin Alexander

    2012-11-27

    }(g)/(g)). Both gamma spectroscopy measurements and the BiPo analysis show the high level of radiopurity reached in Double Chooz. In addition, with the BiPo analysis the {alpha}-quenching factors for the Target and the GammaCatcher liquids have been determined, respectively, to 9.94{+-}0.04 and 13.69{+-}0.02 at 7.7 MeV, and 9.05{+-}0.01 and 14.3{+-}0.1 at 8.8 MeV. The former values show a good agreement with the values obtained in a dedicated laboratory measurement. The time stability of the peak position of the {sup 214}Po {alpha}-peak could be proven, too, showing a stable detector performance at low visible energies. The direct search for Dark Matter can, amongst others, be performed with liquid rare gas detectors, which make use of the scintillation light. However, a good background discrimination is needed. Studies on the wavelength- and time-resolved scintillation properties of liquid argon have therefore been carried out with high resolution and best statistics. The results obtained for different ion beams show that particle discrimination is not feasible in any realistic experiment by means of the wavelength-resolved scintillation light only, but the time structure of the emitted light provides a good handle to distinguish between different incident particles. For heavy ions (sulfur) a ratio of the fast to the slow scintillation component of (1.6 {+-} 0.6) is found, while lighter particles (protons) exhibit a ratio of (0.25 {+-} 0.05). The outcome of the present studies shows that this ratio can also be used in wavelength-integrating measurements which have a comparable detection efficiency for wavelengths below and above {proportional_to}170 nm. The present results demonstrate that for a number of 90 detected photons the singlet-to-triplet distributions obtained for sulfur ions and protons as exciting particles cease to overlap. In a Dark Matter experiment, if all photons produced can be detected, this corresponds to a discrimination threshold of only 2.25 keV.

  6. Liquid scintillators and liquefied rare gases for particle detectors. Background-determination in Double Chooz and scintillation properties of liquid argon

    International Nuclear Information System (INIS)

    Po analysis show the high level of radiopurity reached in Double Chooz. In addition, with the BiPo analysis the α-quenching factors for the Target and the GammaCatcher liquids have been determined, respectively, to 9.94±0.04 and 13.69±0.02 at 7.7 MeV, and 9.05±0.01 and 14.3±0.1 at 8.8 MeV. The former values show a good agreement with the values obtained in a dedicated laboratory measurement. The time stability of the peak position of the 214Po α-peak could be proven, too, showing a stable detector performance at low visible energies. The direct search for Dark Matter can, amongst others, be performed with liquid rare gas detectors, which make use of the scintillation light. However, a good background discrimination is needed. Studies on the wavelength- and time-resolved scintillation properties of liquid argon have therefore been carried out with high resolution and best statistics. The results obtained for different ion beams show that particle discrimination is not feasible in any realistic experiment by means of the wavelength-resolved scintillation light only, but the time structure of the emitted light provides a good handle to distinguish between different incident particles. For heavy ions (sulfur) a ratio of the fast to the slow scintillation component of (1.6 ± 0.6) is found, while lighter particles (protons) exhibit a ratio of (0.25 ± 0.05). The outcome of the present studies shows that this ratio can also be used in wavelength-integrating measurements which have a comparable detection efficiency for wavelengths below and above ∝170 nm. The present results demonstrate that for a number of 90 detected photons the singlet-to-triplet distributions obtained for sulfur ions and protons as exciting particles cease to overlap. In a Dark Matter experiment, if all photons produced can be detected, this corresponds to a discrimination threshold of only 2.25 keV.

  7. Design of a two-phase Xenon TPC for the study of fast scintillation in LXe dark matter detectors

    Energy Technology Data Exchange (ETDEWEB)

    Beskers, Bastian; Grignon, Cyril; Oberlack, Uwe; Othegraven, Rainer; Sissol, Pierre [Johannes Gutenberg Universitaet Mainz (Germany)

    2012-07-01

    XENON100 is currently the most sensitive dark matter search experiment, its successor XENON1T is already in development phase. Dark Matter detectors at the 10 ton scale (e.g. DARWIN) are being envisioned. These experiments are based on dual-phase Xenon time projection chambers. Background suppression and discrimination are driving forces in the design of these experiments. Currently this is accomplished by fiducialization using position sensitivity and light/charge discrimination. Additional discrimination may be achieved by pulse-shape discrimination. The Mainz group is setting up a small two-phase Xenon-TPC to measure charge and scintillation yield at recoil energies in the order of few keV and to study the liquid Xenon scintillation pulse shape. As new features compared to former scintillation/charge yield experiments, our TPC will have 3D position resolution and very fast readout electronics (sampling rate 2.5 GS/s). Position resolution will be used to fiducialize the active volume, select single scatters and to reduce systematic errors. This talk gives an overview on motivation of planned measurements, the simulations done to optimize the design of the TPC and the current state of the experiment.

  8. Design of a two-phase Xenon TPC for the study of fast scintillation in LXe dark matter detectors

    International Nuclear Information System (INIS)

    XENON100 is currently the most sensitive dark matter search experiment, its successor XENON1T is already in development phase. Dark Matter detectors at the 10 ton scale (e.g. DARWIN) are being envisioned. These experiments are based on dual-phase Xenon time projection chambers. Background suppression and discrimination are driving forces in the design of these experiments. Currently this is accomplished by fiducialization using position sensitivity and light/charge discrimination. Additional discrimination may be achieved by pulse-shape discrimination. The Mainz group is setting up a small two-phase Xenon-TPC to measure charge and scintillation yield at recoil energies in the order of few keV and to study the liquid Xenon scintillation pulse shape. As new features compared to former scintillation/charge yield experiments, our TPC will have 3D position resolution and very fast readout electronics (sampling rate 2.5 GS/s). Position resolution will be used to fiducialize the active volume, select single scatters and to reduce systematic errors. This talk gives an overview on motivation of planned measurements, the simulations done to optimize the design of the TPC and the current state of the experiment.

  9. Scintillating glass, fiber-optic plate detectors for active target and tracking applications in high energy physics experiments

    International Nuclear Information System (INIS)

    We have been developing a scintillating glass fiber-optic imaging system for active target and tracking applications in high energy physics experiments. Extensive measurements have been performed on several scintillating-glass compositions, one of which is a silicate-glass containing 0.6 mole % of Ce2O3 known commercially as NRL glass. For this material, fabricated into coherent fiber-optic plates of 10 μm and 25 μm diameter cladded-glass fibers, have observed clear particle tracks and interactions and a yield of about 2 photoelectrons per millimeter of path length for minimum ionizing particles. Additionally, for the bulk NRL glass formed in disks of 1'' diameter and 4 mm thickness, we have observed a about 80% retention of optical transmission through 4 mm of material at 395 mm (the peak of the fluorescence spectrum) for a radiation dose in excess of 107 rads acquired over several days. Results of these tests and others suggest that Ce2O3 based scintillating glasses constitute very promising materials for the fabrication of high resolution tracking detectors for fixed target and colliding beam applications

  10. The ROSPHERE γ-ray spectroscopy array

    Science.gov (United States)

    Bucurescu, D.; Căta-Danil, I.; Ciocan, G.; Costache, C.; Deleanu, D.; Dima, R.; Filipescu, D.; Florea, N.; Ghiţă, D. G.; Glodariu, T.; Ivaşcu, M.; Lică, R.; Mărginean, N.; Mărginean, R.; Mihai, C.; Negret, A.; Niţă, C. R.; Olăcel, A.; Pascu, S.; Sava, T.; Stroe, L.; Şerban, A.; Şuvăilă, R.; Toma, S.; Zamfir, N. V.; Căta-Danil, G.; Gheorghe, I.; Mitu, I. O.; Suliman, G.; Ur, C. A.; Braunroth, T.; Dewald, A.; Fransen, C.; Bruce, A. M.; Podolyák, Zs.; Regan, P. H.; Roberts, O. J.

    2016-11-01

    The ROmanian array for SPectroscopy in HEavy ion REactions (ROSPHERE) has been designed as a multi-detector setup dedicated to γ-ray spectroscopy studies at the Bucharest 9 MV Tandem accelerator. Consisting of up to 25 detectors (either Compton suppressed HPGe detectors or fast LaBr3(Ce) scintillator detectors) together with a state of the art plunger device, ROSPHERE is a powerful tool for lifetime measurements using the Recoil Distance Doppler Shift (RDDS) and the in-beam Fast Electronic Scintillation Timing (FEST) methods. The array's geometry, detectors, electronics and data acquisition system are described. Selected results from the first experimental campaigns are also presented.

  11. High-Speed, Low Power 256 Channel Gamma Radiation Array Detector ASIC Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Building on prior success in detector electronics, we propose to design and fabricate a 256 channel readout ASIC for solid state gamma radiation array detectors...

  12. MUST: A silicon strip detector array for radioactive beam experiments

    CERN Document Server

    Blumenfeld, Y; Sauvestre, J E; Maréchal, F; Ottini, S; Alamanos, N; Barbier, A; Beaumel, D; Bonnereau, B; Charlet, D; Clavelin, J F; Courtat, P; Delbourgo-Salvador, P; Douet, R; Engrand, M; Ethvignot, T; Gillibert, A; Khan, E; Lapoux, V; Lagoyannis, A; Lavergne, L; Lebon, S; Lelong, P; Lesage, A; Le Ven, V; Lhenry, I; Martin, J M; Musumarra, A; Pita, S; Petizon, L; Pollacco, E; Pouthas, J; Richard, A; Rougier, D; Santonocito, D; Scarpaci, J A; Sida, J L; Soulet, C; Stutzmann, J S; Suomijärvi, T; Szmigiel, M; Volkov, P; Voltolini, G

    1999-01-01

    A new and innovative array, MUST, based on silicon strip technology and dedicated to the study of reactions induced by radioactive beams on light particles is described. The detector consists of 8 silicon strip - Si(Li) telescopes used to identify recoiling light charged particles through time of flight, energy loss and energy measurements and to determine precisely their scattering angle through X, Y position measurements. Each 60x60 mm sup 2 double sided silicon strip detector with 60 vertical and 60 horizontal strips yields an X-Y position resolution of 1 mm, an energy resolution of 50 keV, a time resolution of around 1 ns and a 500 keV energy threshold for protons. The backing Si(Li) detectors stop protons up to 25 MeV with a resolution of approximately 50 keV. CsI crystals read out by photo-diodes which stop protons up to 70 MeV are added to the telescopes for applications where higher energy particles need to be detected. The dedicated electronics in VXIbus standard allow us to house the 968 logic and a...

  13. Systematic Study of (d,n Reactions at Ed = 16 MeV Using a Deuterated Scintillator Array

    Directory of Open Access Journals (Sweden)

    Febbraro M.

    2014-03-01

    Full Text Available We have developed a multi-element deuterated liquid scintillator array for the study of reactions involving neutrons utilizing high-speed digital signal processing. A systematic study of (d,n reactions at Ed = 16 MeV on 9Be, 11B, 13C, 14N, 15N, and 19F has been conducted from 10° to 160° (lab. In addition to previously unmeasured back-angle cross sections, this data can complement existing and future (3He,d measurements as an analog to (p,γ for astrophysics applications.

  14. Systematic Study of (d,n) Reactions at Ed = 16 MeV Using a Deuterated Scintillator Array

    OpenAIRE

    Febbraro M.; Becchetti F.D.; Torres-Isea R.O.; Howard A.M.; Riggins A.; Lawrence C.; Kolata J.J.

    2014-01-01

    We have developed a multi-element deuterated liquid scintillator array for the study of reactions involving neutrons utilizing high-speed digital signal processing. A systematic study of (d,n) reactions at Ed = 16 MeV on 9Be, 11B, 13C, 14N, 15N, and 19F has been conducted from 10° to 160° (lab). In addition to previously unmeasured back-angle cross sections, this data can complement existing and future (3He,d) measurements as an analog to (p,γ) for astrophysics applications.

  15. Advanced Antenna-Coupled Superconducting Detector Arrays for CMB Polarimetry

    Science.gov (United States)

    Bock, James

    2014-01-01

    We are developing high-sensitivity millimeter-wave detector arrays for measuring the polarization of the cosmic microwave background (CMB). This development is directed to advance the technology readiness of the Inflation Probe mission in NASA's Physics of the Cosmos program. The Inflation Probe is a fourth-generation CMB satellite that will measure the polarization of the CMB to astrophysical limits, characterizing the inflationary polarization signal, mapping large-scale structure based on polarization induced by gravitational lensing, and mapping Galactic magnetic fields through measurements of polarized dust emission. The inflationary polarization signal is produced by a background of gravitational waves from the epoch of inflation, an exponential expansion of space-time in the early universe, with an amplitude that depends on the physical mechanism producing inflation. The inflationary polarization signal may be distinguished by its unique 'B-mode' vector properties from polarization from the density variations that predominantly source CMB temperature anisotropy. Mission concepts for the Inflation Probe are being developed in the US, Europe and Japan. The arrays are based on planar antennas that provide integral beam collimation, polarization analysis, and spectral band definition in a compact lithographed format that eliminates discrete fore-optics such as lenses and feedhorns. The antennas are coupled to transition-edge superconducting bolometers, read out with multiplexed SQUID current amplifiers. The superconducting sensors and readouts developed in this program share common technologies with NASA X-ray and FIR detector applications. Our program targets developments required for space observations, and we discuss our technical progress over the past two years and plans for future development. We are incorporating arrays into active sub-orbital and ground-based experiments, which advance technology readiness while producing state of the art CMB

  16. Photonic crystals: A novel approach to enhance the light output of scintillation based detectors

    CERN Document Server

    Knapitsch, A; Leclercq, J L; Letartre, X; Auffray, E; Fabjan, C W

    2011-01-01

    Future high-energy physics (HEP) experiments as well as next generation medical imaging applications are more and more pushing towards better scintillation characteristics. One of the problems in heavy scintillating materials is related to their high electronic density, resulting in a large index of refraction. As a consequence, most of the scintillation light produced in the bulk material is trapped inside the crystal due to total internal reflection. The same problem also occurs with light emitting diodes (LEDs) and has for a long time been considered as a limiting factor for their overall efficiency. Recent studies have shown that those limits can be overcome by means of light scattering effects of photonic crystals (PhCs). In our simulations we could show light yield improvements between 90\\% and 110\\% when applying PhC structures to different scintillator materials. To evaluate the results, a PhC modified scintillator was produced in cooperation with the NIL (Nanotechnology Institute of Lyon). By using s...

  17. Capillary Array Waveguide Amplified Fluorescence Detector for mHealth.

    Science.gov (United States)

    Balsam, Joshua; Bruck, Hugh Alan; Rasooly, Avraham

    2013-09-01

    array can potentially be used for sensitive analysis of multiple fluorescent detection assays simultaneously. The simple phone based capillary array approach presented in this paper is capable of amplifying weak fluorescent signals thereby improving the sensitivity of optical detectors based on mobile phones. This may allow sensitive biological assays to be measured with low sensitivity detectors and may make mHealth practical for many diagnostics applications, especially in resource-poor and global health settings.

  18. In-line X-slot element focal plane array of kinetic inductance detectors

    NARCIS (Netherlands)

    Iacono, A.; Freni, A.; Neto, A.; Gerini, G.

    2011-01-01

    Kinetic Inductance Detectors are very promising THz imaging devices to be used in Focal Plane Array configuration. In this work a new antenna feed element has been studied and optimized. Preliminary results on array configuration are also shown.

  19. L3+C air shower array

    CERN Multimedia

    Laurent Guiraud

    2000-01-01

    Photo 01: a view of the L3+C air shower array; 50 scintillators on the roof of the SX-hall above L3. Photo 02: view of one of the detectors of the array.Photo 04: detectors seen against the background of the LEP Point 2 facilities.

  20. Characterization of a GEM-based scintillation detector with He-CF4 gas mixture in clinical proton beams.

    Science.gov (United States)

    Nichiporov, D; Coutinho, L; Klyachko, A V

    2016-04-21

    Accurate, high-spatial resolution dosimetry in proton therapy is a time consuming task, and may be challenging in the case of small fields, due to the lack of adequate instrumentation. The purpose of this work is to develop a novel dose imaging detector with high spatial resolution and tissue equivalent response to dose in the Bragg peak, suitable for beam commissioning and quality assurance measurements. A scintillation gas electron multiplier (GEM) detector based on a double GEM amplification structure with optical readout was filled with a He/CF4 gas mixture and evaluated in pristine and modulated proton beams of several penetration ranges. The detector's performance was characterized in terms of linearity in dose rate, spatial resolution, short- and long-term stability and tissue-equivalence of response at different energies. Depth-dose profiles measured with the GEM detector in the 115-205 MeV energy range were compared with the profiles measured under similar conditions using the PinPoint 3D small-volume ion chamber. The GEM detector filled with a He-based mixture has a nearly tissue equivalent response in the proton beam and may become an attractive and efficient tool for high-resolution 2D and 3D dose imaging in proton dosimetry, and especially in small-field applications. PMID:26992243

  1. Development of InP solid state detector and liquid scintillator containing metal complex for measurement of pp/7Be solar neutrinos and neutrinoless double beta decay

    Science.gov (United States)

    Fukuda, Yoshiyuki; Moriyama, Shigetaka

    2012-07-01

    A large volume solid state detector using a semi-insulating Indium Phosphide (InP) wafer have been developed for measurement of pp/7Be solar neutrinos. Basic performance such as the charge collection efficiency and the energy resolution were measured by 60% and 20%, respectively. In order to detect two gammas (115keV and 497keV) from neutrino capture, we have designed hybrid detector which consist InP detector and liquid xenon scintillator for IPNOS experiment. New InP detector with thin electrode (Cr 50Å- Au 50Å). For another possibility, an organic liquid scintillator containing indium complex and zirconium complex were studied for a measurement of low energy solar neutrinos and neutrinosless double beta decay, respectively. Benzonitrile was chosen as a solvent because of good solubility for the quinolinolato complexes (2 wt%) and of good light yield for the scintillation induced by gamma-ray irradiation. The photo-luminescence emission spectra of InQ3 and ZrQ4 in benzonitrile was measured and liquid scintillator cocktail using InQ3 and ZrQ4 (50mg) in benzonitrile solutions (20 mL) with secondary scintillators with PPO (100mg) and POPOP (10mg) was made. The energy spectra of incident gammas were measured, and they are first results of the gamma-ray energy spectra using luminescent of metal complexes.

  2. An Experiment to Demonstrate Cherenkov / Scintillation Signal Separation

    CERN Document Server

    Caravaca, J; Land, B J; Wallig, J; Yeh, M; Gann, G D Orebi

    2016-01-01

    The ability to separately identify the Cherenkov and scintillation light components produced in scintillating mediums holds the potential for a major breakthrough in neutrino detection technology, allowing development of a large, low-threshold, directional detector with a broad physics program. The CHESS (CHErenkov / Scintillation Separation) experiment employs an innovative detector design with an array of small, fast photomultiplier tubes and state-of-the-art electronics to demonstrate the reconstruction of a Cherenkov ring in a scintillating medium based on photon hit time and detected photoelectron density. This paper describes the physical properties and calibration of CHESS along with first results. The ability to reconstruct Cherenkov rings is demonstrated in a water target, and a time precision of 338 +/- 12 ps FWHM is achieved. Monte Carlo based predictions for the ring imaging sensitivity with a liquid scintillator target predict an efficiency for identifying Cherenkov hits of 94 +/- 1% and 81 +/- 1...

  3. Calibration of scintillation detectors for MeV charged fusion products

    International Nuclear Information System (INIS)

    The light output of ZnS scintillators used to detect escaping fusion products in the TFTR Tokamak is studied with 3.5 MeV alpha and 3 MeV proton beams. The emitted light first increases linearly with beam current and then saturates. In all cases investigated, the onset of the saturation corresponds to a power of about 1 mW absorbed within the ZnS powder. The scintillators have adequate time response up to 50--100 kHz

  4. Development of time-of-flight neutron detector with fast-decay and low-afterglow scintillator for fast ignition experiment

    Directory of Open Access Journals (Sweden)

    Nagai T.

    2013-11-01

    Full Text Available A fast-decay and low-afterglow liquid scintillator was developed for the fast ignition experiment at the Institute of Laser Engineering (ILE. The liquid scintillator was coupled to a gated photomultiplier (PMT, and the gating performance under high-intensity γ-rays was experimentally checked. In 2010, a detector with a high detection efficiency of 10−4 was developed and installed in this experiment. The neutron yield in the fast heating experiment was successfully measured using this detector.

  5. Mechanical Design and Development of TES Bolometer Detector Arrays for the Advanced ACTPol Experiment

    Science.gov (United States)

    Ward, Jonathan T.; Austermann, Jason; Beall, James A.; Choi, Steve K.; Crowley, Kevin T.; Devlin, Mark J.; Duff, Shannon M.; Gallardo, Patricio M.; Henderson, Shawn W.; Ho, Shuay-Pwu Patty; Hilton, Gene; Hubmayr, Johannes; Khavari, Niloufar; Klein, Jeffrey; Koopman, Brian J.; Li, Dale; McMahon, Jeffrey; Mumby, Grace; Nati, Federico; Wollack, Edward J.

    2016-01-01

    The next generation Advanced ACTPol (AdvACT) experiment is currently underway and will consist of four Transition Edge Sensor (TES) bolometer arrays, with three operating together, totaling 5800 detectors on the sky. Building on experience gained with the ACTPol detector arrays, AdvACT will utilize various new technologies, including 150 mm detector wafers equipped with multichroic pixels, allowing for a more densely packed focal plane. Each set of detectors includes a feedhorn array of stacked silicon wafers which form a spline pro le leading to each pixel. This is then followed by a waveguide interface plate, detector wafer, back short cavity plate, and backshort cap. Each array is housed in a custom designed structure manufactured from high purity copper and then gold plated. In addition to the detector array assembly, the array package also encloses cryogenic readout electronics. We present the full mechanical design of the AdvACT high frequency (HF) detector array package along with a detailed look at the detector array stack assemblies. This experiment will also make use of extensive hardware and software previously developed for ACT, which will be modi ed to incorporate the new AdvACT instruments. Therefore, we discuss the integration of all AdvACT arrays with pre-existing ACTPol infrastructure.

  6. Electrical breakdown gas detector featuring carbon nanotube array electrodes.

    Science.gov (United States)

    Kim, Seongyul; Pal, Sunil; Ajayan, Pulickel M; Borca-Tasciuc, Theodorian; Koratkar, Nikhil

    2008-01-01

    We demonstrate here detection of dichloro-difluoro-methane and oxygen in mixtures with helium using a carbon nanotube electrical breakdown sensor device. The sensor is comprised of an aligned array of multiwalled carbon nanotubes deposited on a nickel based super-alloy (Inconel 600) as the anode; the counter electrode is a planar nickel sheet. By monitoring the electrical breakdown characteristics of oxygen and dichloro-difluoro-methane in a background of helium, we find that the detection limit for dichloro-difluoro-methane is approximately 0.1% and the corresponding limit for oxygen is approximately 1%. A phenomenologigal model is proposed to describe the trends observed in detection of the two mixtures. These results indicate that carbon nanotube based electrical breakdown sensors show potential as end detectors in gas-chromatography devices. PMID:18468093

  7. Thermal crosstalk simulation and measurement of linear terahertz detector arrays

    Science.gov (United States)

    Li, Weizhi; Huang, Zehua; Wang, Jun; Li, Mingyu; Gou, Jun; Jiang, Yadong

    2015-11-01

    Thermal simulation of differently structured linear terahertz detector arrays (TDAs) based on lithium tantalate was performed by finite element analysis (FEA). Simulation results revealed that a relatively simple TDA structure can have good thermal insulation, i.e., low thermal crosstalk effect (TCE), between adjacent pixels, which was thus selected for the real fabrication of TDA sample. Current responsivity (Ri) of the sample for a 2.52 THz source was measured to be 6.66 × 10-6 A/W and non-uniformity (NU) of Ri was 4.1%, showing good performance of the sample. TCE test result demonstrated that small TCE existed in the sample, which was in good agreement with the simulation results.

  8. Ultracold neutron detection with 6Li-doped glass scintillators, NANOSC: a fast ultracold neutron detector for the nEDM experiment at the Paul Scherrer Institute

    CERN Document Server

    Ban, G; Bodek, K; Chowdhuri, Z; Geltenbort, P; Griffith, W C; Hélaine, V; Henneck, R; Kasprzak, M; Kermaidic, Y; Kirch, K; Komposch, S; Koss, P A; Kozela, A; Krempel, J; Lauss, B; Lefort, T; Lemière, Y; Mtchedlishvili, A; Musgrave, M; Naviliat-Cuncic, O; Piegsa, F M; Pierre, E; Pignol, G; Quéméner, G; Rawlik, M; Ries, D; Rebreyend, D; Roccia, S; Rogel, G; Schmidt-Wellenburg, P; Severijns, N; Wursten, E; Zejma, J; Zsigmond, G

    2016-01-01

    This paper summarizes the results from measurements aiming to characterize ultracold neutron detection with 6Li-doped glass scintillators. Single GS10 or GS20 scintillators, with a thickness of 100-200 micrometer, fulfill the ultracold neutron detection requirements with an acceptable neutron-gamma discrimination. This discrimination is clearly improved with a stack of two scintillators: a 6Li-depleted glass bonded to a 6Li-enriched glass. The optical contact bonding is used between the scintillators in order to obtain a perfect optical contact. The scintillator's detection efficiency is similar to that of a 3He Strelkov gas detector. Coupled to a digital data acquisition system, counting rates up to a few 10^5 counts/s can be handled. A detector based on such a scintillator stack arrangement was built and has been used in the neutron electric dipole moment experiment at the Paul Scherrer Institute since 2010. Its response for the regular runs of the neutron electric dipole moment experiment is presented.

  9. Characterization of a GEM-based scintillation detector with He-CF4 gas mixture in clinical proton beams

    Science.gov (United States)

    Nichiporov, D.; Coutinho, L.; Klyachko, A. V.

    2016-04-01

    Accurate, high-spatial resolution dosimetry in proton therapy is a time consuming task, and may be challenging in the case of small fields, due to the lack of adequate instrumentation. The purpose of this work is to develop a novel dose imaging detector with high spatial resolution and tissue equivalent response to dose in the Bragg peak, suitable for beam commissioning and quality assurance measurements. A scintillation gas electron multiplier (GEM) detector based on a double GEM amplification structure with optical readout was filled with a He/CF4 gas mixture and evaluated in pristine and modulated proton beams of several penetration ranges. The detector’s performance was characterized in terms of linearity in dose rate, spatial resolution, short- and long-term stability and tissue-equivalence of response at different energies. Depth-dose profiles measured with the GEM detector in the 115-205 MeV energy range were compared with the profiles measured under similar conditions using the PinPoint 3D small-volume ion chamber. The GEM detector filled with a He-based mixture has a nearly tissue equivalent response in the proton beam and may become an attractive and efficient tool for high-resolution 2D and 3D dose imaging in proton dosimetry, and especially in small-field applications.

  10. The VXI electronics of the DIAMANT particle detector array

    International Nuclear Information System (INIS)

    A VXI card designed for the processing of signals from the particle detector array DIAMANT, a CsI(Tl) light charged particle ancillary detector system to the EUROBALL and the EXOGAM gamma-spectrometers, is described. The card provides particle energy, particle-type and time-reference information and is compatible with the existing signal-processing system of EUROBALL/EXOGAM. In order to have full compatibility with the electronics of these spectrometers without sacrificing the performance of the card, some new solutions are used in the signal processing. For particle discrimination three methods can be selected; the ballistic deficit method, the zero-crossing method and a combination of these two methods. The figure of merit of the particle discrimination using the combined method is better than that of the zero crossing or the ballistic deficit method individually. Timing signals for particle-gamma coincidence are derived by a specially designed non-delay-line constant fraction discriminator, which exhibits low rise-time-dependent walk. The card has been tested with EUROBALL. The results of these tests are presented

  11. SU-E-T-423: TrueBeam Small Field Dosimetry Using Commercial Plastic Scintillation and Other Stereotactic Detectors

    International Nuclear Information System (INIS)

    Purpose: To perform dose profile and output factor (OF) measurements with the Exradin W1 plastic scintillation detector (PSD) for small fields made by the high-definition multi-leaf collimator (MLC) on the TrueBeam STx system and to compare them to values measured with an IBA CC01 ionization chamber and a Sun Nuclear Edge detector diode for 6 MV photon beams. Methods: The Exradin W1 is a new small volume near-water equivalent and energy independent PSD manufactured by Standard Imaging, Inc. All measurements were performed in an IBA Blue Phantom water tank. Square MLC-shaped fields with sides ranging from 0.5 cm to 2 cm and jawshaped fields with sides ranging from 1 cm to 40 cm were measured using an SAD setup at 10 cm depth. Dose profile and percent depth dose (PDD) measurements were also taken under the same conditions for MLC fields 0.5×0.5 and 1×1 cm2 in size with jaws at 2×2cm2. The CC01 and W1 were vertically mounted. Results: OFs measured with the W1 for jaw only square fields were consistent with the ones measured with a Farmers PTW TN33013 ion chamber (1.8% maximum deviation). OF and penumbra measurement results are presented below. PDDs measured for all detectors are within 1.5% for the 0.5×0.5 cm2 and within 1% for the 1×1 cm2 MLC fields.Output factors:MLC size W1 CC01 EDGE0.5cm 0.555 0.541 0.5851.0cm 0.716 0.702 0.7331.5cm 0.779 0.761 0.7772.0cm 0.804 0.785 0.796Penumbras (mm):MLC size W1 CC01 EDGE0.5cm 2.7 2.9 2.51.0cm 3.0 3.4 2. Conclusion: OFs measured for small MLC fields were consistent with the ones measured with the other stereotactic detectors. Measured penumbras are consistent with detector size. The Exradin W1 PSD is an excellent choice for characterizing MLC-shaped small beam dosimetry used for stereotactic radiosurgery and body radiation therapy. Sam Beddar would like to disclose a NIH/NCI SBIR Phase II grant (2R44CA153824-02A1) with Standard Imaging, Title: “Water-Equivalent Plastic Scintillation Detectors for Small Field

  12. Silicon photomultipliers for scintillating trackers

    Energy Technology Data Exchange (ETDEWEB)

    Rabaioli, S., E-mail: simone.rabaioli@gmail.com [Universita degli Studi dell' Insubria, Via Valleggio, 11 - 22100 Como (Italy); Berra, A.; Bolognini, D. [Universita degli Studi dell' Insubria, Via Valleggio, 11 - 22100 Como (Italy); INFN sezione di Milano Bicocca (Italy); Bonvicini, V. [INFN sezione di Trieste (Italy); Bosisio, L. [Universita degli Studi di Trieste and INFN sezione di Trieste (Italy); Ciano, S.; Iugovaz, D. [INFN sezione di Trieste (Italy); Lietti, D. [Universita degli Studi dell' Insubria, Via Valleggio, 11 - 22100 Como (Italy); INFN sezione di Milano Bicocca (Italy); Penzo, A. [INFN sezione di Trieste (Italy); Prest, M. [Universita degli Studi dell' Insubria, Via Valleggio, 11 - 22100 Como (Italy); INFN sezione di Milano Bicocca (Italy); Rashevskaya, I.; Reia, S. [INFN sezione di Trieste (Italy); Stoppani, L. [Universita degli Studi dell' Insubria, Via Valleggio, 11 - 22100 Como (Italy); Vallazza, E. [INFN sezione di Trieste (Italy)

    2012-12-11

    In recent years, silicon photomultipliers (SiPMs) have been proposed as a new kind of readout device for scintillating detectors in many experiments. A SiPM consists of a matrix of parallel-connected pixels, which are independent photon counters working in Geiger mode with very high gain ({approx}10{sup 6}). This contribution presents the use of an array of eight SiPMs (manufactured by FBK-irst) for the readout of a scintillating bar tracker (a small size prototype of the Electron Muon Ranger detector for the MICE experiment). The performances of the SiPMs in terms of signal to noise ratio, efficiency and time resolution will be compared to the ones of a multi-anode photomultiplier tube (MAPMT) connected to the same bars. Both the SiPMs and the MAPMT are interfaced to a VME system through a 64 channel MAROC ASIC.

  13. Silicon photomultipliers for scintillating trackers

    Science.gov (United States)

    Rabaioli, S.; Berra, A.; Bolognini, D.; Bonvicini, V.; Bosisio, L.; Ciano, S.; Iugovaz, D.; Lietti, D.; Penzo, A.; Prest, M.; Rashevskaya, I.; Reia, S.; Stoppani, L.; Vallazza, E.

    2012-12-01

    In recent years, silicon photomultipliers (SiPMs) have been proposed as a new kind of readout device for scintillating detectors in many experiments. A SiPM consists of a matrix of parallel-connected pixels, which are independent photon counters working in Geiger mode with very high gain (∼106). This contribution presents the use of an array of eight SiPMs (manufactured by FBK-irst) for the readout of a scintillating bar tracker (a small size prototype of the Electron Muon Ranger detector for the MICE experiment). The performances of the SiPMs in terms of signal to noise ratio, efficiency and time resolution will be compared to the ones of a multi-anode photomultiplier tube (MAPMT) connected to the same bars. Both the SiPMs and the MAPMT are interfaced to a VME system through a 64 channel MAROC ASIC.

  14. Development of a scintillation-fiber detector for real-time particle tracking

    Science.gov (United States)

    Lo Presti, D.; Bonanno, D. L.; Longhitano, F.; Pugliatti, C.; Russo, G. V.; Aiello, S.; Cirrone, G. A. P.; Giordano, V.; Leonora, E.; Randazzo, N.; Romano, F.; Russo, M.; Sipala, V.; Stancampiano, C.; Reito, S.

    2013-04-01

    The prototype of the OFFSET (Optical Fiber Folded Scintillating Extended Tracker) tracker is presented. It exploits a novel system for particle tracking, designed to achieve real-time imaging, large detection areas, and a high spatial resolution especially suitable for use in medical diagnostics. The main results regarding the system architecture have been used as a demonstration of the technique which has been patented by the Istituto Nazionale di Fisica Nucleare (INFN). The prototype of this tracker, presented in this paper, has a 20 × 20 cm2 sensitive area, consisting of two crossed ribbons of 500 micron square scintillating fibers. The track position information is extracted in real time in an innovative way, using a reduced number of read-out channels to obtain very large detection area with moderate enough costs and complexity. The performance of the tracker was investigated using beta sources, cosmic rays, and a 62 MeV proton beam.

  15. Development of a scintillation-fiber detector for real-time particle tracking

    International Nuclear Information System (INIS)

    The prototype of the OFFSET (Optical Fiber Folded Scintillating Extended Tracker) tracker is presented. It exploits a novel system for particle tracking, designed to achieve real-time imaging, large detection areas, and a high spatial resolution especially suitable for use in medical diagnostics. The main results regarding the system architecture have been used as a demonstration of the technique which has been patented by the Istituto Nazionale di Fisica Nucleare (INFN). The prototype of this tracker, presented in this paper, has a 20 × 20 cm2 sensitive area, consisting of two crossed ribbons of 500 micron square scintillating fibers. The track position information is extracted in real time in an innovative way, using a reduced number of read-out channels to obtain very large detection area with moderate enough costs and complexity. The performance of the tracker was investigated using beta sources, cosmic rays, and a 62 MeV proton beam.

  16. Scintillation properties of undoped CdS for ionizing radiation detectors

    Science.gov (United States)

    Yanagida, Takayuki; Koshimizu, Masanori; Okada, Go

    2016-02-01

    In the present study, nondoped CdS crystal with a size of 5 × 5 × 0.5 mm3 was investigated on the optical and scintillation properties. The optical transmittance was 70% at wavelength longer than 500 nm, and the absorption edge was around 490 nm. The photoluminescence emission peak appeared around 490 nm under 340 nm excitation with 6.6 ns fast decay time. In X-ray induced radioluminescence spectrum over the temperature range of 7-300 K, it showed four emission bands around 490, 500-540 with several peaks, 600, and 750 nm. Temperature dependences of each emission band were different. The scintillation decay time was reproduced by two exponential decay components of 8 and 67 ns, and that for X-ray induced afterglow was approximately 0.1% at 20 ms after switching of the X-ray irradiation.

  17. Scintillation detector using an europium-doped calcium fluoride single crystal

    Energy Technology Data Exchange (ETDEWEB)

    Gilar, O.; Pavlicek, Z.; Jursova, L. (Tesla, Premysleni (Czechoslovakia). Vyzkumny Ustav Pristroju Jaderne Techniky)

    1981-06-01

    A europium-doped calcium fluoride monocrystal-based scintillator is suitable for detecting X, alpha, beta and low-energy gamma radiations. It is resistant to thermal and mechanical shocks. Its outstanding physical properties include the index of refraction of 1.443. The results are reported of measuring the spectra of selected radionuclides and the energy resolution dependence on the gamma radiation energy.

  18. Spectral modeling of scintillator for the NEMO-3 and SuperNEMO detectors

    OpenAIRE

    Argyriades, J.; Arnold, R.; Augier, C.; Baker, J.; Barabash, A. S.; Bongrand, M.; Broudin-Bay, G.; Brudanin, V. B.; Caffrey, A. J.; Cebrián, S; Chapon, A.; Chauveau, E.; Dafni, Th.; Daraktchieva, Z.; iaz, J. D

    2010-01-01

    We have constructed a GEANT4-based detailed software model of photon transport in plastic scintillator blocks and have used it to study the NEMO-3 and SuperNEMO calorimeters employed in experiments designed to search for neutrinoless double beta decay. We compare our simulations to measurements using conversion electrons from a calibration source of $\\rm ^{207}Bi$ and show that the agreement is improved if wavelength-dependent properties of the calorimeter are taken into account. In this arti...

  19. O5S, Calibration of Organic Scintillation Detector by Monte-Carlo

    International Nuclear Information System (INIS)

    1 - Nature of physical problem solved: O5S is designed to directly simulate the experimental techniques used to obtain the pulse height distribution for a parallel beam of mono-energetic neutrons incident on organic scintillator systems. Developed to accurately calibrate the nominally 2 in. by 2 in. liquid organic scintillator NE-213 (composition CH-1.2), the programme should be readily adaptable to many similar problems. 2 - Method of solution: O5S is a Monte Carlo programme patterned after the general-purpose Monte Carlo neutron transport programme system, O5R. The O5S Monte Carlo experiment follows the course of each neutron through the scintillator and obtains the energy-deposits of the ions produced by elastic scatterings and reactions. The light pulse produced by the neutron is obtained by summing up the contributions of the various ions with the use of appropriate light vs. ion-energy tables. Because of the specialized geometry and simpler cross section needs O5S is able to by-pass many features included in O5R. For instance, neutrons may be followed individually, their histories analyzed as they occur, and upon completion of the experiment, the results analyzed to obtain the pulse-height distribution during one pass on the computer. O5S does allow the absorption of neutrons, but does not allow splitting or Russian roulette (biased weighting schemes). SMOOTHIE is designed to smooth O5S histogram data using Gaussian functions with parameters specified by the user

  20. SU-E-T-476: Quality Assurance for Gamma Knife Perfexion Using the Exradin W1 Plastic Scintillation Detector

    Energy Technology Data Exchange (ETDEWEB)

    Pino, R [Houston Methodist Hospital (United States); Therriault-Proulx, F; Yang, J; Beddar, S [University of Texas MD Anderson Cancer Center, Houston, TX (United States)

    2014-06-01

    Purpose: To perform dose profile and output factor measurements for the Exradin W1 plastic scintillation detector (PSD) for the Gamma Knife Perfexion (GKP) collimators in a Lucy phantom and to compare these values to an Exradin A16 ion chamber, EBT3 radiochromic film and treatment planning system (TPS) data. Methods: We used the Exradin W1 PSD which has a small volume, near-water equivalent sensitive element. It has also been shown to be energy independent. This new detector is manufactured and distributed by Standard Imaging, Inc. Measurements were performed for all three collimators (4 mm, 8 mm and 16 mm) for the GKP. The Lucy phantom with the PSD inserted was moved in small steps to acquire profiles in all three directions. EBT3 film was inserted in the Lucy phantom and exposed to a single shot for each collimator. Relative output factors were measured using the three detectors while profiles acquired with the PSD were compared to the ones measured with EBT3 radiochromic film. Results: Measured output factors relative to the largest collimator are as followsCollimator PS EBT3 A1616mm 1.000 1.000 1.0008mm 0.892 0.881 0.8834mm 0.795 0.793 0.727 The nominal (vendor) OFs for GKP are 1.000, 0.900, and 0.814, for collimators 16 mm, 8 mm and 4 mm, respectively. There is excellent agreement between all profiles measured with the PSD and EBT3 as well as with the TPS data provided by the vendor. Conclusion: Output factors measured with the W1 were consistent with the ones measured with EBT3 and A16 ion chamber. Measured profiles are in excellent agreement. The W1 detector seems well suited for beam QA for Gamma Knife due to its dosimetric characteristics. Sam Beddar would like to disclose a NIH/NCI SBIR Phase II grant (2R44CA153824-02A1) with Standard Imaging, Title: “Water-Equivalent Plastic Scintillation Detectors for Small Field Radiotherapy”.