磷化铟(In P)作为第二代化合物半导体材料,抗辐照能力强,光电转换效率高,在光子领域和射频领域具有优势.大气空间中, In P半导体器件受大气中子辐照影响,器件性能发生退化.本文采用蒙特卡罗模拟软件Geant4对In P中子辐照效应进行模拟,得...磷化铟(In P)作为第二代化合物半导体材料,抗辐照能力强,光电转换效率高,在光子领域和射频领域具有优势.大气空间中, In P半导体器件受大气中子辐照影响,器件性能发生退化.本文采用蒙特卡罗模拟软件Geant4对In P中子辐照效应进行模拟,得到In P中不同能量中子产生的位移损伤初态分布.结果表明:在微米量级内,非电离能量损失(NIEL)随深度均匀分布,在厘米及更高量级上, NIEL随着入射深度的增大而降低,当靶材料足够厚时可以降低至零;分析1—20 Me V中子入射3μm In P产生的NIEL及其随深度分布,发现NIEL随入射中子能量的增加呈现出先升后降的趋势,该趋势主要由非弹性散射反应产生的初级反冲原子(PKA)造成;分析1—20 Me V中子入射3μm In P产生的PKA种类、能量,发现In/P的PKA占比较大,是产生位移损伤的主要因素,中子能量越高, PKA的种类越丰富, PKA最大动能越大,但PKA主要分布在低能部分.研究结果对In P基5G器件在大气中子辐射环境中的长期应用具有理论和指导价值.展开更多
The deuteron breakup on heavy targets has been investigated in the framework of an improved quantum molecular dynamics model,focusing on the production of neutrons near zero degrees.The experimental differential cross...The deuteron breakup on heavy targets has been investigated in the framework of an improved quantum molecular dynamics model,focusing on the production of neutrons near zero degrees.The experimental differential cross sections of neutron production in the 102 MeV d+C reactions were reproduced by simulations.Based on the consistency between the model prediction and experiment,the feasibility of producing a neutron beam through the breakup of deuteron on a carbon target was demonstrated.Because of the nucleon Fermi motion inside the deuteron,the energy spectrum of the inclusive neutron near 0°in the laboratory exhibits considerable energy broadening in the main peak,whereas the long tail on the low-energy side is suppressed.By coincidentally measuring the accompanying deuteron breakup proton,the energy of the neutron can be tagged with an intrinsic uncertainty of approximately 5%(1σ).The tagging efficiency of the accompanying proton on the forward-emitted neutron can reach 90%,which ensures that the differential cross section in the(d,np)channel remains two orders higher than that in(p,n)after considering the measurement of accompanying protons.This enables the application of a well-defined energy neutron beam in an event-by-event scheme.展开更多
To further investigate the fusion neutron source based on a gas dynamic trap （GDT）, characteristics of the GDT were analyzed and physics analyses were made for a fusion neutron source based on the GDT concept. The p...To further investigate the fusion neutron source based on a gas dynamic trap （GDT）, characteristics of the GDT were analyzed and physics analyses were made for a fusion neutron source based on the GDT concept. The prior design of a GDT-based fusion neutron source was optimized based on a refreshed understanding of GDT operation. A two-step progressive development route of a GDT-based fusion neutron source was suggested. Potential applications of GDT are discussed. Preliminary analyses show that a fusion neutron source based on the GDT concept is suitable for plasma-material interaction research, fusion material and subcomponent testing, and capable of driving a proof-of-principle fusion fission hybrid experimental facility.展开更多
We discuss current attempts to employ the modified potential cluster model to describe the available experimental data on the^(13)B(n,γ0+1)^(14)B total cross-sections.The estimated results of the M1 and E1 transition...We discuss current attempts to employ the modified potential cluster model to describe the available experimental data on the^(13)B(n,γ0+1)^(14)B total cross-sections.The estimated results of the M1 and E1 transitions from the n^(13)B scattering states to the ground and first excited states of^(14)B are presented.The 1st resonance at Ex=1.275 MeV(1+)is revealed in both the cross-section and reaction rate.Within the variation in the asymptotic constant,a thermal cross-section interval of 5.1-8.9 mb is proposed.Based on the theoretical total cross-sections at energies of 0.01 eV to 5 MeV,we calculate the reaction rate in the temperature range of 0.01 to 10T9.The ignition T9 values of the^(13)B(n,γ0+1)^(14)B reaction depending on a neutron number density n_(n)of~10^(22)cm^(−3)are determined.The radiative neutron capture reaction rates on the boron^(10-13)B and carbon^(12-14)Сisotopes are compared.展开更多
Utilizing the PYTHIA8 Angantyr model,which incorporates the multiple-parton interaction(MPI)based color reconnection(CR)mechanism,we study the relative neutron density fluctuation and neutron-proton correlation in Au+...Utilizing the PYTHIA8 Angantyr model,which incorporates the multiple-parton interaction(MPI)based color reconnection(CR)mechanism,we study the relative neutron density fluctuation and neutron-proton correlation in Au+Au collisions at√sNN=7.7,11.5,14.5,19.6,27,39,62.4,and 200 GeV.In this study,we not only delve into the dependence of these two remarkable observations on rapidity,centrality,and energy,but also analyze their interplay with the MPI and CR.Our results show that the light nuclei yield ratio of protons,deuterons,and tritons,expressed by the elegant expression N_(t)N_(p)/N^(d)^(2),remains unchanged even as the rapidity coverage and collision centrality increase.Interestingly,we also reveal that the effect of CR is entirely dependent on the presence of the MPI;CR has no impact on the yield ratio if the MPI is off.Our findings further demonstrate that the light nuclei yield ratio experiences a slight increase with increasing collision energy,as predicted by the PYTHIA8 Angantyr model;however,it cannot describe the non-monotonic trend observed by the STAR experiment.Based on the Angantyr model simulation results,it is essential not to overlook the correlation between neutron and proton fluctuations.The Angantyr model is a good baseline for studying collisions in the absence of a quark-gluon plasma system,given its lack of flow and jet quenching.展开更多
A single width NIM module that includes eight channels of the time-to-amplitude converter （TAC） and the charge-to-amplitude converter （QAC） is introduced in the paper, which is designed for the large neutron wall ...A single width NIM module that includes eight channels of the time-to-amplitude converter （TAC） and the charge-to-amplitude converter （QAC） is introduced in the paper, which is designed for the large neutron wall detector to measure charge （energy） and time interval simultaneously. The module adopts a high precision gated integration circuit to realize TAC and QAC. ：The input range of TAC is from 30 ns to 1 μs, and the input range of QAC is from 40 pC to 600 pC. The linearity error of TAC is lower than 1.28%, and the time resolution of TAC is less than 0.871%. The linearity error of QAC is lower than 0.81%, and the resolution of QAC is better than 0.936%.展开更多
Measuring the pionic structure function is of high interest, as it provides a new area for understanding the strong interaction among quarks and testing QCD predictions. To this end, we investigate the feasibility and...Measuring the pionic structure function is of high interest, as it provides a new area for understanding the strong interaction among quarks and testing QCD predictions. To this end, we investigate the feasibility and expected impact of a possible experiment at EicC(Electron-ion collider in China). We show the simulation results on the statistical precision of an EicC measurement, based on the model of leading neutron tagged DIS process and the parton distribution functions of the pion from JAM18 global analysis. The simulation shows that at EicC, the kinematics cover the x π range from 0.01 to 1, and the Q2 range from 1 to 50 GeV2, within the acceptable statistical uncertainty. Assuming an integrated luminosity of 50 fb-1, in the low-Q2 region(< 10 GeV2), the Monte Carlo data show that the suggested measurement in the whole x π range reaches very high precision(< 3%). To perform such an experiment, only the addition of a far-forward neutron calorimeter is needed.展开更多
The BESⅢCollaboration has recently published a new precise measurement of the time-like neutron form factor(FF)[1].In the light of the remarkable accuracy and of the wideness of the explored kinematical range,these d...The BESⅢCollaboration has recently published a new precise measurement of the time-like neutron form factor(FF)[1].In the light of the remarkable accuracy and of the wideness of the explored kinematical range,these data represent an unprecedented tool for highlighting and studying specific features of the neutron FF.Until a few years ago,the only available data were those obtained by the FENICE experiment at Frascati,in the’90s[2].展开更多
文摘磷化铟(In P)作为第二代化合物半导体材料,抗辐照能力强,光电转换效率高,在光子领域和射频领域具有优势.大气空间中, In P半导体器件受大气中子辐照影响,器件性能发生退化.本文采用蒙特卡罗模拟软件Geant4对In P中子辐照效应进行模拟,得到In P中不同能量中子产生的位移损伤初态分布.结果表明:在微米量级内,非电离能量损失(NIEL)随深度均匀分布,在厘米及更高量级上, NIEL随着入射深度的增大而降低,当靶材料足够厚时可以降低至零;分析1—20 Me V中子入射3μm In P产生的NIEL及其随深度分布,发现NIEL随入射中子能量的增加呈现出先升后降的趋势,该趋势主要由非弹性散射反应产生的初级反冲原子(PKA)造成;分析1—20 Me V中子入射3μm In P产生的PKA种类、能量,发现In/P的PKA占比较大,是产生位移损伤的主要因素,中子能量越高, PKA的种类越丰富, PKA最大动能越大,但PKA主要分布在低能部分.研究结果对In P基5G器件在大气中子辐射环境中的长期应用具有理论和指导价值.
基金supported by the National Natural Science Foundation of China(Nos.11961141004,11605119,11965004,12047567,and U1867212)the Jiangsu Natural Science Fund Youth Project(No.BK20160304)+1 种基金China Postdoctoral Science Foundation(No.2017M621818)the Ministry of Science and Technology(No.2020YFE0202001).
文摘The deuteron breakup on heavy targets has been investigated in the framework of an improved quantum molecular dynamics model,focusing on the production of neutrons near zero degrees.The experimental differential cross sections of neutron production in the 102 MeV d+C reactions were reproduced by simulations.Based on the consistency between the model prediction and experiment,the feasibility of producing a neutron beam through the breakup of deuteron on a carbon target was demonstrated.Because of the nucleon Fermi motion inside the deuteron,the energy spectrum of the inclusive neutron near 0°in the laboratory exhibits considerable energy broadening in the main peak,whereas the long tail on the low-energy side is suppressed.By coincidentally measuring the accompanying deuteron breakup proton,the energy of the neutron can be tagged with an intrinsic uncertainty of approximately 5%(1σ).The tagging efficiency of the accompanying proton on the forward-emitted neutron can reach 90%,which ensures that the differential cross section in the(d,np)channel remains two orders higher than that in(p,n)after considering the measurement of accompanying protons.This enables the application of a well-defined energy neutron beam in an event-by-event scheme.
基金supported by the IAEA Coordinate Research Project F1.30.15 Conceptual Development of Steady-State Compact Fusion Neutron Sources,the Knowledge Innovation Projects of Chinese Academy of Sciences(No.KJCX2-YW-N37)National Magnetic Confinement Fusion Science Program of China(No.2011GB114004)
文摘To further investigate the fusion neutron source based on a gas dynamic trap （GDT）, characteristics of the GDT were analyzed and physics analyses were made for a fusion neutron source based on the GDT concept. The prior design of a GDT-based fusion neutron source was optimized based on a refreshed understanding of GDT operation. A two-step progressive development route of a GDT-based fusion neutron source was suggested. Potential applications of GDT are discussed. Preliminary analyses show that a fusion neutron source based on the GDT concept is suitable for plasma-material interaction research, fusion material and subcomponent testing, and capable of driving a proof-of-principle fusion fission hybrid experimental facility.
基金the Ministry of Science and Higher Education of the Republic of Kazakhstan(AP09259174)。
文摘We discuss current attempts to employ the modified potential cluster model to describe the available experimental data on the^(13)B(n,γ0+1)^(14)B total cross-sections.The estimated results of the M1 and E1 transitions from the n^(13)B scattering states to the ground and first excited states of^(14)B are presented.The 1st resonance at Ex=1.275 MeV(1+)is revealed in both the cross-section and reaction rate.Within the variation in the asymptotic constant,a thermal cross-section interval of 5.1-8.9 mb is proposed.Based on the theoretical total cross-sections at energies of 0.01 eV to 5 MeV,we calculate the reaction rate in the temperature range of 0.01 to 10T9.The ignition T9 values of the^(13)B(n,γ0+1)^(14)B reaction depending on a neutron number density n_(n)of~10^(22)cm^(−3)are determined.The radiative neutron capture reaction rates on the boron^(10-13)B and carbon^(12-14)Сisotopes are compared.
基金Supported in part by the Natural Science Foundation of Henan Province,China (212300410386)the Key Research Projects of Henan Higher Education Institutions (20A140024)+3 种基金the Scientific Research Foundation of Hubei University of Education for Talent Introduction (ESRC20220028,ESRC20230002)the NSFC(12005114)NSFC key Grant (12061141008)the Key Laboratory of Quark and Lepton Physics (MOE) in the Central China Normal University(QLPL2022P01)
文摘Utilizing the PYTHIA8 Angantyr model,which incorporates the multiple-parton interaction(MPI)based color reconnection(CR)mechanism,we study the relative neutron density fluctuation and neutron-proton correlation in Au+Au collisions at√sNN=7.7,11.5,14.5,19.6,27,39,62.4,and 200 GeV.In this study,we not only delve into the dependence of these two remarkable observations on rapidity,centrality,and energy,but also analyze their interplay with the MPI and CR.Our results show that the light nuclei yield ratio of protons,deuterons,and tritons,expressed by the elegant expression N_(t)N_(p)/N^(d)^(2),remains unchanged even as the rapidity coverage and collision centrality increase.Interestingly,we also reveal that the effect of CR is entirely dependent on the presence of the MPI;CR has no impact on the yield ratio if the MPI is off.Our findings further demonstrate that the light nuclei yield ratio experiences a slight increase with increasing collision energy,as predicted by the PYTHIA8 Angantyr model;however,it cannot describe the non-monotonic trend observed by the STAR experiment.Based on the Angantyr model simulation results,it is essential not to overlook the correlation between neutron and proton fluctuations.The Angantyr model is a good baseline for studying collisions in the absence of a quark-gluon plasma system,given its lack of flow and jet quenching.
基金Supported by National Natural Science Foundation of China(11005135,11079045)National Instruments Special of China(2011YQ12009604)
文摘A single width NIM module that includes eight channels of the time-to-amplitude converter （TAC） and the charge-to-amplitude converter （QAC） is introduced in the paper, which is designed for the large neutron wall detector to measure charge （energy） and time interval simultaneously. The module adopts a high precision gated integration circuit to realize TAC and QAC. ：The input range of TAC is from 30 ns to 1 μs, and the input range of QAC is from 40 pC to 600 pC. The linearity error of TAC is lower than 1.28%, and the time resolution of TAC is less than 0.871%. The linearity error of QAC is lower than 0.81%, and the resolution of QAC is better than 0.936%.
基金the Strategic Priority Research Program of Chinese Academy of Sciences(XDB34030301)。
文摘Measuring the pionic structure function is of high interest, as it provides a new area for understanding the strong interaction among quarks and testing QCD predictions. To this end, we investigate the feasibility and expected impact of a possible experiment at EicC(Electron-ion collider in China). We show the simulation results on the statistical precision of an EicC measurement, based on the model of leading neutron tagged DIS process and the parton distribution functions of the pion from JAM18 global analysis. The simulation shows that at EicC, the kinematics cover the x π range from 0.01 to 1, and the Q2 range from 1 to 50 GeV2, within the acceptable statistical uncertainty. Assuming an integrated luminosity of 50 fb-1, in the low-Q2 region(< 10 GeV2), the Monte Carlo data show that the suggested measurement in the whole x π range reaches very high precision(< 3%). To perform such an experiment, only the addition of a far-forward neutron calorimeter is needed.
文摘The BESⅢCollaboration has recently published a new precise measurement of the time-like neutron form factor(FF)[1].In the light of the remarkable accuracy and of the wideness of the explored kinematical range,these data represent an unprecedented tool for highlighting and studying specific features of the neutron FF.Until a few years ago,the only available data were those obtained by the FENICE experiment at Frascati,in the’90s[2].
