A new inorganic scintillation material based on Ba-Gd silica glass doped with cerium (BGS) is fabricated and studied. With the highest light yield among heavy glasses at the level of 2500 ph/MeV and ...fast scintillation response, the new scintillator ensures a good coincidence time resolution of < 230 ps FWHM for 511 keV γ-quanta from a 22Na source and SiPM readout. In addition to good performance in γ-quanta detection, the material demonstrates capability for efficient detection of low-energetic neutrons. The scintillator is produced by exploiting the standard industrial glass technology, which allows for an unlimited scaling up the conversion of raw material into a high-quality scintillator at a high rate. The glass can be casted in application-specific molds, so minimizing the material losses. The presented glass scintillator has potential for further improvement of its light output and scintillation response time.
The application of crystalline materials in ionizing radiation detectors has played a crucial role in the discovery of the properties of matter. However, the experiences gathered at high intensity ...machines such as the LHC have indicated their limitations and underlined the requirements for materials being more tolerable to radiation damage in particular caused by energetic hadrons. Systematic studies of the radiation hardness of inorganic optical and scintillation materials propose both oxide and fluoride crystals composed of atoms with atomic numbers below 60. In this study we report on a cheap glass (BaO*2SiO2) and DSB: Ce glass ceramics even capable for mass production. Admixing gadolinium oxide (Gd3+) even provides a two times larger light yield. Both types of the materials can be produced in a fibre and bulk geometry. This paper summarizes the overall performance and reports on a first test of a 3x3 matrix of large volume samples exposed to energy-marked photons up to 180 MeV.
The development of novel scintillators for ionizing radiation detectors is still playing a significant role in high-energy physics, medical and homeland security applications. New detector concepts ...require a unique combination of the material properties like rising and decay times, light output and in the case of collider experiments the radiation hardness. cerium doped garnet type scintillation materials have been intensively developed in the last years. Among them, Y 3 Al 5 O 12 (YAG), Lu 3 Al 5 O 12 (LuAG) and Gd 3 Al 2 Ga 3 O 12 (GAGG) with high radiation hardness recognized for both gamma- and proton irradiation, were found to be the most promising materials. Many modern detector systems based on scintillation materials require high-count rates. This involves the use of bright scintillators with fast rise and decay times in combination with modern ultra-fast photodetectors such as SiPMs. A possible solution for such kind of applications is a family of lutetium-yttrium oxyorthosilicates (Lu 2(1-x) Y 2x SiO5, LSO, LYSO, YSO). Here we report on the characterization of different types of garnets with various dopants and in shapes of pixels and bulk and on the study of properties of LSO, LYSO, YSO solely doped by Ce as well LYSO materials with Ca and Mg co-doping from different producers.
Abstract The PANDA (antiProton ANnihilation at DArmstadt) experiment will study the strong interaction in annihilation reactions between an antiproton beam and a stationary cluster jet target. The ...PANDA detector will be composed of several sub-detectors designed for tracking, particle identification and calorimetry. The Micro-Vertex Detector (MVD) is the innermost part of the tracking system surrounding the interaction region, which is designed for precise vertex and tracking detection. It consists of silicon pixel and double-sided microstrip detectors. For the readout of the microstrip sensors an ASIC called ToASt (Torino Asic for Strip readout) is being developed in 0.11 μm CMOS technology at INFN Turin. The ASIC takes advantage of both Time-over-Threshold and Time-of-Arrival methods to accurately measure the event's energy and timestamp. To sustain the acquisition of the microstrip sensors a MDC (Module Data Concentrator) ASIC is under development at KIT. Up to eight ToASt front-ends' data streams are multiplexed, read out and processed by one MDC. The data of several MDCs are collected and processed by the off-detector readout card MMB (MVD Multiplexer Board), also under development at KIT. The processed data is then transferred via 100 GbE optical links to the computing nodes. The ToASt chips have been integrated with the FPGA implementation of the MDC to form the first fully functional detector module. Beam tests have been performed at the COSY facility in Jülich. This paper focuses on the design of MDC ASIC and MMB board, the integration with the ToASt and presents preliminary beam test results.
The lead tungstate crystal (PbWO 4 , PWO) is one of the widely used scintillation materials for electromagnetic calorimeters (EMCs) in high-energy physics experiments. The degradation of the optical ...transmittance in the range of the luminescence spectrum under ionizing radiation leads to losses of the light output resulting in the deterioration of the energy resolution and limiting the lifetime of the calorimeter. A possible way to restore radiation damage is the in situ illumination by visible or near-infrared light of the whole crystal volume. It allows recovering the transmittance losses due to the depopulation of the color centers. Such a kind of stimulated recovery subsystem based on a blue light-emitting diode is considered for the EMC of the PANDA detector at Facility for Antiproton and Ion Research (FAIR) (Darmstadt, Germany). Here, we report on the stimulated recovery studies of the lead tungstate radiation damage induced by external light from laser diodes at different wavelengths. The level of technological development of laser diodes allows increasing the efficiency of the stimulated recovery.
The scintillator gadolinium aluminium gallium garnet (Gd3Al2Ga3O12, GAGG) was found to be an excellent material for application in non-homogeneous detecting cells for future calorimeters, operating ...in a harsh irradiation environment. GAGG, activated by cerium ions, can be used to detect γ-quanta and to absorb efficiently neutrons in a wide energy range. The capture of neutrons is accompanied by the emission of relatively soft γ-quanta which can be ignored at calorimetric measurements above 10 MeV. These findings create prospects to construct compact detectors for different purposes, from particle physics to industry.
Lead Tungstate (PbWO 4 , PWO) has become presently the most commonly used scintillator material for electromagnetic calorimetry in medium and high-energy physics. There exists substantial demand for ...future calorimeters such as the completion of the PANDA electromagnetic compatibility (EMC) as well as various detector projects under discussion at Jefferson Lab or Brookhaven National Laboratory in the United States. Nearly, 6700 crystals are missing for the barrel section of the PANDA-EMC since the successful mass production of PWO using the Czochralski method was stopped after bankruptcy of the Bogoroditsk Technical Chemical Plant (BTCP) in Russia. Intermediate research and development efforts with the Shanghai Institute of Ceramics, Chinese Academy of Science, Shanghai, China, as an existing producer exploiting the modified Bridgman method could not reach the required quality in a consistent manner. End of 2014, the CRYTUR (Turnov, Czech Republic) has restarted the development of lead tungstate based again on the Czochralski method with impressive progress. The modified and optimized technology has already produced full size samples of PWO-II quality. This paper will present a detailed status report on a first preproduction run of 89 crystals focusing on the achieved optical performance, light yield, kinetics, and temperature dependence and radiation hardness.
This report presents results on the significant improvement of GAGG:Ce based scintillation detector performance with temperature decrease. When temperature of a PMT based detector is lowered to ...−45 °C, its amplitude response at registration of γ-quanta is improved by 30%; FHHM was found to be better up to factor of 0.85, whereas scintillation kinetics become even faster in crystals co-doped with magnesium and magnesium and titanium. All this opens an opportunity for a wide application of GAGG scintillation detectors, particularly in a combination with SiPM photo-sensors, which signal-to-noise ratio would also improve with temperature decrease.
Abstract
We studied the light yield of a pure polystyrene slide
coated with wavelength-shifter molecules, coupled to a
photomultiplier, using
β
-
particles from a
90
Sr
source, as a possible ...easy-to-build, low-cost plastic scintillator
detector. Comparison measurements were performed with an uncoated
polystyrene slide as well as with uncoated and coated PMMA slides,
the latter which can only produce Cherenkov light when being
traversed by charged particles. The results with the single (double)
coated polystyrene slides show about 4.9 (6.3) times higher detected
photon yield compared to the uncoated slide. For comparison, the
light yield of a polystyrene-based extruded plastic scintillator
material doped with PTP and POPOP was measured as well. The
absolute detected light yield motivates future studies for
developing easy-to-build, low-cost polystyrene-based plastic
scintillator detectors.
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