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
With the aim of simulating the harsh temperature condition of space, a thallium-activated cesium iodide crystal(CsI:Tl) detector readout with a PIN photodiode(CsI:Tl(PD)) and with a silicon photomultiplier(CsI:Tl(SiPM...With the aim of simulating the harsh temperature condition of space, a thallium-activated cesium iodide crystal(CsI:Tl) detector readout with a PIN photodiode(CsI:Tl(PD)) and with a silicon photomultiplier(CsI:Tl(SiPM)) is investigated over a temperature range from-40 to 40 ℃. With the increase in temperature, the output signal increases by ～ 24% with CsI:Tl(PD) and decreases by ～69% with CsI:Tl(SiPM). To reduce the effect of temperature in outer space, a method of bias voltage compensation is adopted for CsI:Tl(SiPM). Our study demonstrates that after correcting the temperature the variation in the analog-to-digital converter's amplitude is< 3%.展开更多
Large-sized CsI（Tl） single crystals, -φ 0100 mm×350 mm, have been grown successfully, and this CsI（Tl） coupled with PD has been successfully utilized at RIBLL （the Radioactive Ion Beam Line in Lanzhou） to ...Large-sized CsI（Tl） single crystals, -φ 0100 mm×350 mm, have been grown successfully, and this CsI（Tl） coupled with PD has been successfully utilized at RIBLL （the Radioactive Ion Beam Line in Lanzhou） to measure the energy of heavy ions as a stopping detector. The performances of CsI（Tl） detector coupled with PD and APD have been tested and compared, including the temperature dependence of scintillating light yield.展开更多
We investigated the cathode luminescence characteristics of CsI(Na)and CsI(Tl)crystals by the spectrum and structure properties at room temperature.We fabricated three different sizes of CsI(Na)and CsI(Tl)crystals and...We investigated the cathode luminescence characteristics of CsI(Na)and CsI(Tl)crystals by the spectrum and structure properties at room temperature.We fabricated three different sizes of CsI(Na)and CsI(Tl)crystals and measured their luminescence spectra under cathode rays.We found that CsI(Na)cathode luminescence peaks appear at 420 and 305 nm,and CsI(Tl)cathode luminescence peaks are 540 and 410 nm,the grain size affects CsI(Na)luminescence significantly,and the Na-related420 nm luminescence intensified relatively when the average grain size reaches^20μm,which becomes weak when the grain size is down to nano-scale.But the cathode luminescence spectra of CsI(Tl)crystals with different size have no obvious changes.Our explanations for these phenomena are that the different impurities in the same host material CsI lead to different luminescence mechanisms.These cathode luminescence characteristics indicate the suitability of CsI(Na)and CsI(Tl)crystals to match photomultiplier tube for large area crystal detector development.展开更多
To investigate the configurations of the valence protons in Borromean nucleus 17Ne, a CsI(Tl) detector array, which consists of 9 CsI crystals (26×26×20mm3) coupled with photodiodes, has been successfully us...To investigate the configurations of the valence protons in Borromean nucleus 17Ne, a CsI(Tl) detector array, which consists of 9 CsI crystals (26×26×20mm3) coupled with photodiodes, has been successfully used in the 17Ne experiment to measure the energy of protons. In order to find the optimal working conditions and get the best energy resolutions, several technologies (including various wrapping materials, wrapping and coupling methods) have been used. The testing results showed that the best energy resolution of the CsI(Tl) is about 3.3% using the 241Am α-source. The primary testing results with the proton beam were also provided.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%.
基金supported by the National Natural Science Foundation of China(Nos.11575257,11575269,and U1732134)the Youth Innovation Promotion Association of the Chinese Academy of Science(No.2015342)
文摘With the aim of simulating the harsh temperature condition of space, a thallium-activated cesium iodide crystal(CsI:Tl) detector readout with a PIN photodiode(CsI:Tl(PD)) and with a silicon photomultiplier(CsI:Tl(SiPM)) is investigated over a temperature range from-40 to 40 ℃. With the increase in temperature, the output signal increases by ～ 24% with CsI:Tl(PD) and decreases by ～69% with CsI:Tl(SiPM). To reduce the effect of temperature in outer space, a method of bias voltage compensation is adopted for CsI:Tl(SiPM). Our study demonstrates that after correcting the temperature the variation in the analog-to-digital converter's amplitude is< 3%.
基金Supported by Knowledge Innovation Project of Chinese Academy of Sciences (CKJCX2-SW-N18,CKJCX2-SW-N04)
文摘Large-sized CsI（Tl） single crystals, -φ 0100 mm×350 mm, have been grown successfully, and this CsI（Tl） coupled with PD has been successfully utilized at RIBLL （the Radioactive Ion Beam Line in Lanzhou） to measure the energy of heavy ions as a stopping detector. The performances of CsI（Tl） detector coupled with PD and APD have been tested and compared, including the temperature dependence of scintillating light yield.
基金supported by the Fundamental Research Funds for the Central Universities(Grant No.11QG14)
文摘We investigated the cathode luminescence characteristics of CsI(Na)and CsI(Tl)crystals by the spectrum and structure properties at room temperature.We fabricated three different sizes of CsI(Na)and CsI(Tl)crystals and measured their luminescence spectra under cathode rays.We found that CsI(Na)cathode luminescence peaks appear at 420 and 305 nm,and CsI(Tl)cathode luminescence peaks are 540 and 410 nm,the grain size affects CsI(Na)luminescence significantly,and the Na-related420 nm luminescence intensified relatively when the average grain size reaches^20μm,which becomes weak when the grain size is down to nano-scale.But the cathode luminescence spectra of CsI(Tl)crystals with different size have no obvious changes.Our explanations for these phenomena are that the different impurities in the same host material CsI lead to different luminescence mechanisms.These cathode luminescence characteristics indicate the suitability of CsI(Na)and CsI(Tl)crystals to match photomultiplier tube for large area crystal detector development.
基金Supported by National Natural Science Foundation of China (10775005, 10735010, J0730316)Chinese Major State Basic Research Development Program (2007CB815002)
文摘To investigate the configurations of the valence protons in Borromean nucleus 17Ne, a CsI(Tl) detector array, which consists of 9 CsI crystals (26×26×20mm3) coupled with photodiodes, has been successfully used in the 17Ne experiment to measure the energy of protons. In order to find the optimal working conditions and get the best energy resolutions, several technologies (including various wrapping materials, wrapping and coupling methods) have been used. The testing results showed that the best energy resolution of the CsI(Tl) is about 3.3% using the 241Am α-source. The primary testing results with the proton beam were also provided.
