Total absorption gamma-ray spectroscopy(TAGS)is a powerful tool for measuring complexγ transitions,which has been effectively applied to the study of reactor decay heat.This paper presents the design of a new TAGS de...Total absorption gamma-ray spectroscopy(TAGS)is a powerful tool for measuring complexγ transitions,which has been effectively applied to the study of reactor decay heat.This paper presents the design of a new TAGS detector,the large-scale modular BGO detection array(LAMBDA),tailored for measuringβ-decay intensity distributions of fission products.The modular design allows the LAMBDA detectors to be assembled in various configurations.The final version of LAMBDA consists of 102 identical 60 mm×60 mm×120 mm BGO crystals and exhibits a high full-energy peak efficiency exceeding 80%at 0.5∼8 MeV based on a Monte Carlo simulation.Currently,approximately half of the LAMBDA modules have been manufactured.Tests usingγ-ray sources and nuclear reactions demonstrated favorable energy resolution,energy linearity,and efficiency uniformity across the modules.Forty-eight modules have been integrated into the prototype LAMBDA-I.The capability of LAMBDA-I inβ-delayedγ-decay experiments was evaluated by commissioning measurements using the ^(152)Eu source.展开更多
In this study,we present a new method for the indirect integration of beam charges in external beam proton-induced X-ray emission and proton-induced c-ray emission(PIXE–PIGE) analysis.We recorded proton spectra backs...In this study,we present a new method for the indirect integration of beam charges in external beam proton-induced X-ray emission and proton-induced c-ray emission(PIXE–PIGE) analysis.We recorded proton spectra backscattered by a Kapton film extraction window in different sample situations and under different beam currents.We also simulated backscattering spectra using the simulation of backscattering spectra program(SIMNRA).We determined that in a specific geometrical arrangement,different sample situations did not significantly affect factor C_Q(the ratio between integral backscattering proton counts and integral beam charges).We also studied the reproducibility and beam current dependence of factor C_Q.The statistic factor of C_Q was28.95 ± 0.6 kilo counts/l C,with a relative standard deviation of 2.0 %.Significantly,in external beam PIXE–PIGE analysis,we were able to calculate beam charge integration from the integral backscattering proton counts in an energy region.展开更多
It is of particular interest to investigate nuclear fusion reactions generated by high-intensity lasers in plasma environments that are similar to real astrophysical conditions.We have experimentally investigated2H(d,...It is of particular interest to investigate nuclear fusion reactions generated by high-intensity lasers in plasma environments that are similar to real astrophysical conditions.We have experimentally investigated2H(d,p)3H,one of the most crucial reactions in big bang nucleosynthesis models,at the Shenguang-Ⅱlaser facility.In this work,we present a new calibration of CR-39 solidstate track detectors,which are widely employed as the main diagnostics in this type of fusion reaction experiment.We measure the dependence of the track diameter on the proton energy.It is found that the track diameters of protons with different energies are likely to be identical.We propose that in this case,the energy of the reaction products can be obtained by considering both the diameters and gray levels of these tracks.The present results would be very helpful for analyzing the2 H(d,p)3H reaction products recorded with the same batch of CR-39 solid-state track detectors.展开更多
To understand the evolution of defects in SiC during irradiation and the influence of temperature,in situ luminescence measurements of 6H-SiC crystal samples were carried out by ion beam induced luminescence(IBIL)meas...To understand the evolution of defects in SiC during irradiation and the influence of temperature,in situ luminescence measurements of 6H-SiC crystal samples were carried out by ion beam induced luminescence(IBIL)measurement under2 MeV H^+ at 100 K,150 K,200 K,250 K,and 300 K.A wide band(400-1000 nm)was found in the spectra at all temperatures,and the intensity of the IBIL spectra was highest at 150 K among the five temperatures.A small peak from 400 nm to 500 nm was only observed at 100 K,related with the D1 defect as a donor-acceptor pair(D-A)recombination.For further understanding the luminescent centers and their evolution,the orange band(1.79 eV)and the green band(2.14 eV)in the energy spectrum were analyzed by Gaussian decomposition,maybe due to the donor-deep defect/conduction band-deep defect transitions and Ti related bound excition,respectively.Finally,a single exponential fit showed that when the temperature exceeded 150 K,the two luminescence centers’resistance to radiation was reduced.展开更多
基金supported by the National Key R&D Program of China (Nos. 2022YFA1603300, 2018YFA0404401, 2023YFA1606701, and 2022YFA1602301)National Natural Science Foundation of China (Nos. U1867211, 12275026, and 12222514)the CAS Light of West China Program (No. 2020-82)
文摘Total absorption gamma-ray spectroscopy(TAGS)is a powerful tool for measuring complexγ transitions,which has been effectively applied to the study of reactor decay heat.This paper presents the design of a new TAGS detector,the large-scale modular BGO detection array(LAMBDA),tailored for measuringβ-decay intensity distributions of fission products.The modular design allows the LAMBDA detectors to be assembled in various configurations.The final version of LAMBDA consists of 102 identical 60 mm×60 mm×120 mm BGO crystals and exhibits a high full-energy peak efficiency exceeding 80%at 0.5∼8 MeV based on a Monte Carlo simulation.Currently,approximately half of the LAMBDA modules have been manufactured.Tests usingγ-ray sources and nuclear reactions demonstrated favorable energy resolution,energy linearity,and efficiency uniformity across the modules.Forty-eight modules have been integrated into the prototype LAMBDA-I.The capability of LAMBDA-I inβ-delayedγ-decay experiments was evaluated by commissioning measurements using the ^(152)Eu source.
基金supported by the Beijing Natural Science Funds(No.1142006)
文摘In this study,we present a new method for the indirect integration of beam charges in external beam proton-induced X-ray emission and proton-induced c-ray emission(PIXE–PIGE) analysis.We recorded proton spectra backscattered by a Kapton film extraction window in different sample situations and under different beam currents.We also simulated backscattering spectra using the simulation of backscattering spectra program(SIMNRA).We determined that in a specific geometrical arrangement,different sample situations did not significantly affect factor C_Q(the ratio between integral backscattering proton counts and integral beam charges).We also studied the reproducibility and beam current dependence of factor C_Q.The statistic factor of C_Q was28.95 ± 0.6 kilo counts/l C,with a relative standard deviation of 2.0 %.Significantly,in external beam PIXE–PIGE analysis,we were able to calculate beam charge integration from the integral backscattering proton counts in an energy region.
基金This work was supported by the National Key Research and Development Project(No.2016YFA0400502)the National Natural Science Foundation of China(No.11775312).
文摘It is of particular interest to investigate nuclear fusion reactions generated by high-intensity lasers in plasma environments that are similar to real astrophysical conditions.We have experimentally investigated2H(d,p)3H,one of the most crucial reactions in big bang nucleosynthesis models,at the Shenguang-Ⅱlaser facility.In this work,we present a new calibration of CR-39 solidstate track detectors,which are widely employed as the main diagnostics in this type of fusion reaction experiment.We measure the dependence of the track diameter on the proton energy.It is found that the track diameters of protons with different energies are likely to be identical.We propose that in this case,the energy of the reaction products can be obtained by considering both the diameters and gray levels of these tracks.The present results would be very helpful for analyzing the2 H(d,p)3H reaction products recorded with the same batch of CR-39 solid-state track detectors.
基金Project supported by the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.11905010)the Fundamental Research Funds for the Central Universities,China(Grant No.2018NTST04)+1 种基金the China Postdoctoral Science Foundation(Grant No.2019M650526)Guangdong Province Key Area R&D Program,China(Grant No.2019B090909002)。
文摘To understand the evolution of defects in SiC during irradiation and the influence of temperature,in situ luminescence measurements of 6H-SiC crystal samples were carried out by ion beam induced luminescence(IBIL)measurement under2 MeV H^+ at 100 K,150 K,200 K,250 K,and 300 K.A wide band(400-1000 nm)was found in the spectra at all temperatures,and the intensity of the IBIL spectra was highest at 150 K among the five temperatures.A small peak from 400 nm to 500 nm was only observed at 100 K,related with the D1 defect as a donor-acceptor pair(D-A)recombination.For further understanding the luminescent centers and their evolution,the orange band(1.79 eV)and the green band(2.14 eV)in the energy spectrum were analyzed by Gaussian decomposition,maybe due to the donor-deep defect/conduction band-deep defect transitions and Ti related bound excition,respectively.Finally,a single exponential fit showed that when the temperature exceeded 150 K,the two luminescence centers’resistance to radiation was reduced.
