The measurement of high-energy γ-rays is an important experimental method to study the giant resonance in a nucleus, c reaction in nuclear astrophysics, and so on. The performance of a large-size Cs I detector for cr...The measurement of high-energy γ-rays is an important experimental method to study the giant resonance in a nucleus, c reaction in nuclear astrophysics, and so on. The performance of a large-size Cs I detector for crays detection is studied by comparison between the experimental measurements and GEANT4 simulation. The reliability of the simulated efficiency for low-energy γ-rays is verified by comparing with the experimental data. The efficiency of the Cs I detector for high-energy γ-rays was obtained by the GEANT4 simulation. The simulation shows that the detection efficiency of 20 Me V γ-rays can reach 3.8%.展开更多
介绍了配置于新型γ能谱仪的CsI(Tl)闪烁探测器的读出电路设计。输入缓冲级采用折叠嵌位电路,改善了系统频率特性并提高了输入阻抗;放大级采用自举电路,改善了系统动态性能并提高了开环增益;输出级采用电流源负载电路,改善了输出信号的...介绍了配置于新型γ能谱仪的CsI(Tl)闪烁探测器的读出电路设计。输入缓冲级采用折叠嵌位电路,改善了系统频率特性并提高了输入阻抗;放大级采用自举电路,改善了系统动态性能并提高了开环增益;输出级采用电流源负载电路,改善了输出信号的线性度并增强了系统的稳定性。实验表明:读出电路噪声为51.08 f C+1.97 f C/p F,时间漂移为0.112%,探头对137Cs源γ射线的输出信号信噪比可达23:1,能量分辨率可达4.98%。展开更多
The Gamma-ray Transient Monitor(GTM) is an all-sky monitor onboard the Distant Retrograde Orbit-A(DRO-A) satellite with the scientific objective of detecting gamma-ray transients ranging from 20 ke V to 1 MeV. The GTM...The Gamma-ray Transient Monitor(GTM) is an all-sky monitor onboard the Distant Retrograde Orbit-A(DRO-A) satellite with the scientific objective of detecting gamma-ray transients ranging from 20 ke V to 1 MeV. The GTM was equipped with five Gamma-ray Transient Probe(GTP) detector modules utilizing a NaI(Tl) scintillator coupled with a SiPM array. To reduce the SiPM noise, GTP uses a dedicated dual-channel coincident readout design. In this work, we first studied the impact of different coincidence times on the detection efficiency and ultimately selected a 0.5 μs time coincidence window for offline data processing. To test the performance of the GTPs and validate the Monte-Carlo-simulated energy response, we conducted comprehensive ground calibration tests using the Hard X-ray Calibration Facility(HXCF) and radioactive sources, including the energy response, detection efficiency, spatial response, bias-voltage response, and temperature dependence. We extensively present the ground calibration results and validate the design and mass model of the GTP detector, thus providing the foundation for in-flight observations and scientific data analysis.展开更多
基金supported by the Major State Basic Research Development Program of China(No.2013CB834405)the National Natural Science Foundation of China(Nos.11421505,11475244,and 11175231)
文摘The measurement of high-energy γ-rays is an important experimental method to study the giant resonance in a nucleus, c reaction in nuclear astrophysics, and so on. The performance of a large-size Cs I detector for crays detection is studied by comparison between the experimental measurements and GEANT4 simulation. The reliability of the simulated efficiency for low-energy γ-rays is verified by comparing with the experimental data. The efficiency of the Cs I detector for high-energy γ-rays was obtained by the GEANT4 simulation. The simulation shows that the detection efficiency of 20 Me V γ-rays can reach 3.8%.
文摘介绍了配置于新型γ能谱仪的CsI(Tl)闪烁探测器的读出电路设计。输入缓冲级采用折叠嵌位电路,改善了系统频率特性并提高了输入阻抗;放大级采用自举电路,改善了系统动态性能并提高了开环增益;输出级采用电流源负载电路,改善了输出信号的线性度并增强了系统的稳定性。实验表明:读出电路噪声为51.08 f C+1.97 f C/p F,时间漂移为0.112%,探头对137Cs源γ射线的输出信号信噪比可达23:1,能量分辨率可达4.98%。
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant Nos.XDA30050100 and XDA30030000)the National Natural Science Foundation of China (Grant Nos.12173038,11775251,12273042,and 12075258)funded by the Strategic Priority Research Program on Space Science (Grant No.XDA15360000) of the Chinese Academy of Sciences (CAS)。
文摘The Gamma-ray Transient Monitor(GTM) is an all-sky monitor onboard the Distant Retrograde Orbit-A(DRO-A) satellite with the scientific objective of detecting gamma-ray transients ranging from 20 ke V to 1 MeV. The GTM was equipped with five Gamma-ray Transient Probe(GTP) detector modules utilizing a NaI(Tl) scintillator coupled with a SiPM array. To reduce the SiPM noise, GTP uses a dedicated dual-channel coincident readout design. In this work, we first studied the impact of different coincidence times on the detection efficiency and ultimately selected a 0.5 μs time coincidence window for offline data processing. To test the performance of the GTPs and validate the Monte-Carlo-simulated energy response, we conducted comprehensive ground calibration tests using the Hard X-ray Calibration Facility(HXCF) and radioactive sources, including the energy response, detection efficiency, spatial response, bias-voltage response, and temperature dependence. We extensively present the ground calibration results and validate the design and mass model of the GTP detector, thus providing the foundation for in-flight observations and scientific data analysis.
