Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userEnergy response of GECAM Gamma-Ray Detector (GRD) prototype
167
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
The Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) , composed of two small satellites, is a new mission to monitor the Gamma-Ray Bursts (GRBs) coincident with gravitational wave events with a FOV of 100% all-sky. GECAM detects and localizes 6 keV-5 MeV GRBs via 25 compact and novel Gamma-Ray Detectors (GRDs). Each GRD module is comprised of a LaBr3:Ce scintillator, SiPM array and preamplifier. A large dynamic range is achieved by the high gain and low gain channels of the preamplifier. This article discusses the performance of a GRD prototype which includes a set of radioactive sources in the range of 5.9-1332.5 keV. The energy resolution and energy to ADC channel conversion of the GRD module are also discussed. The typical energy resolution is 5.3% at 662 keV (FWHM) which meets the relevant requirements (< 8% at 662 keV). The energy calibration capability is evaluated by the measured intrinsic activity of LaBr3:Ce and Geant4 simulation results. The test results demonstrate the feasibility of the GECAM GRD design.
rate research
Read More
The hyperspectral X-ray imaging has been long sought in various fields from material analysis to medical diagnosis. Here we propose a new semiconductor detector structure to realize energy-resolved imaging at potentially low cost. The working principle is based on the strong energy-dependent absorption of X-ray in solids. Namely, depending on the energy, X-ray photons experience dramatically different attenuation. An array or matrix of semiconductor cells is to map the X-ray intensity along its trajectory. The X-ray spectrum could be extracted from a Laplace like transform or even a supervised machine learning. We demonstrated an energy-resolved X-ray detection with a regular silicon camera.
We have studied neutron response of PARIS phoswich [LaBr$_3$(Ce)-NaI(Tl)] detector which is being developed for measuring the high energy (E$_{gamma}$ = 5 - 30 MeV) $gamma$ rays emitted from the decay of highly collective states in atomic nuclei. The relative neutron detection efficiency of LaBr$_3$(Ce) and NaI(Tl) crystal of the phoswich detector has been measured using the time-of-flight (TOF) and pulse shape discrimination (PSD) technique in the energy range of E$_n$ = 1 - 9 MeV and compared with the GEANT4 based simulations. It has been found that for E$_n$ $>$ 3 MeV, $sim$ 95 % of neutrons have the primary interaction in the LaBr$_3$(Ce) crystal, indicating that a clear n-$gamma$ separation can be achieved even at $sim$15 cm flight path.
Geant4 simulations play a crucial role in the analysis and interpretation of experiments providing low energy precision tests of the Standard Model. This paper focuses on the accuracy of the description of the electron processes in the energy range between 100 and 1000 keV. The effect of the different simulation parameters and multiple scattering models on the backscattering coefficients is investigated. Simulations of the response of HPGe and passivated implanted planar Si detectors to beta{} particles are compared to experimental results. An overall good agreement is found between Geant4 simulations and experimental data.
The main scientific goal of the Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) is to monitor various types of Gamma-Ray Bursts (GRB) originated from merger of binary compact stars, which could also produce gravitational wave, and collapse of massive stars. In order to study the response of GECAM Gamma-Ray Detectors (GRDs) to high-energy bursts and test the in-flight trigger and localization software of GECAM before the launch, a portable GRB simulator device is designed and implemented based on grid controlled X-ray tube (GCXT) and direct digital synthesis (DDS) technologies. The design of this GRB simulator which modulates X-ray flux powered by high voltage up to 20 kV is demonstrated, and the time jitter (FWHM) of the device is about 0.9 $mu$s. Before the launch in December, 2020, both two GECAM satellites were irradiated by different types of GRBs (including short and long bursts in duration) generated by this GRB simulator. The light curves detected with GECAM/GRDs are consistent with the programmed input functions within statistical uncertainties, indicating the good performance of both the GRDs and the GRB simulator.
At NISER-IoP detector laboratory an initiative is taken to build and test Gas Electron Multiplier (GEM) detectors for ALICE experiment. The optimisation of the gas flow rate and the long-term stability test of the GEM detector are performed. The method and test results are presented.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
