In this study, the activation cross-sections were measured for ^(232)Th(n,2n)^(231)Th reactions at neutron energies of 14.1 and 14.8 MeV, which were produced by a neutron generator through a T(d,n)~4He reaction. Induc...In this study, the activation cross-sections were measured for ^(232)Th(n,2n)^(231)Th reactions at neutron energies of 14.1 and 14.8 MeV, which were produced by a neutron generator through a T(d,n)~4He reaction. Induced gamma-ray activities were measured using a low background gamma ray spectrometer equipped with a high resolution HPGe detector. In the cross-section calculations, corrections were made regarding the effects of gamma-ray attenuation, dead-time, fluctuation of the neutron flux, and low energy neutrons. The measured cross-sections were compared with the literature data, evaluation data(ENDF-B/VII.1, JENDL-4.0 and CENDL-3.1), and the results of the model calculation(TALYS1.6).展开更多
A three-wave based laser polarimeter/interferometer and a CO_(2)laser dispersion interferometer are used to determine the electron and current density profiles on a Chinese fusion engineering test reactor(CFETR).Radia...A three-wave based laser polarimeter/interferometer and a CO_(2)laser dispersion interferometer are used to determine the electron and current density profiles on a Chinese fusion engineering test reactor(CFETR).Radiation shielding is designed for the combination of polarimeter/interferometer and CO_(2)dispersion interferometer.Furthermore,neutronics models of the two systems are developed based on the engineering-integrated design of CFETR polarimeter/interferometer and CO_(2)dispersion interferometer and the major material components of CFETR.The polarimeter/interferometer and CO_(2)dispersion interferometer's neutron and photon transport simulations were performed using the Monte Carlo neutral transport code to determine the energy deposition and neutron energy spectrum of the optical mirrors.The energy depositions of the first mirrors on the polarimeter/interferometer are reduced by three orders with the whole shielding.Since the mirrors of CO_(2)dispersion interferometer are very close to the diagnostic first wall,shielding space is limited and the CO_(2)dispersion interferometer energy deposition is higher than that of the polarimeter/interferometer.The dose rate after shutdown106s in the back-drawer structure has been estimated to be 83μSv h^(-1)when the radiation shield is filled in the diagnostic shielding modules,which is below the design threshold of 100μSv h^(-1).Radiation shielding design plays a key role in successfully applying polarimeter/interferometer and CO_(2)dispersive interferometer in CFETR.展开更多
The thick target neutron yields (TTNYs) of deuteron-induced reaction on AI and Cu isotopes are analyzed by combining the improved nuclear models and particle transport effects. The modified Glauber model is employed...The thick target neutron yields (TTNYs) of deuteron-induced reaction on AI and Cu isotopes are analyzed by combining the improved nuclear models and particle transport effects. The modified Glauber model is employed mainly to produce the peak of double differential cross section for the breakup process, and the exciton model and the Hauser-Feshbach theory are used for the statistical processes. The thin-layer accumulation method is used to calculate the TTNYs considering the neutron attenuation effects in the target. The calculated results are compared with the existing experimental data, and the analysis method can predict the TTNY data well at the deuteron energy of 40 MeV.展开更多
基金Supported by National Natural Science Foundation of China(No.11205076)
文摘In this study, the activation cross-sections were measured for ^(232)Th(n,2n)^(231)Th reactions at neutron energies of 14.1 and 14.8 MeV, which were produced by a neutron generator through a T(d,n)~4He reaction. Induced gamma-ray activities were measured using a low background gamma ray spectrometer equipped with a high resolution HPGe detector. In the cross-section calculations, corrections were made regarding the effects of gamma-ray attenuation, dead-time, fluctuation of the neutron flux, and low energy neutrons. The measured cross-sections were compared with the literature data, evaluation data(ENDF-B/VII.1, JENDL-4.0 and CENDL-3.1), and the results of the model calculation(TALYS1.6).
基金the National MCF Energy R&D Program of China(Nos.2019YFE03040003 and 2017YFE0301205)Key Program of Research and Development of Hefei Science Center,CAS(No.2019HSC-KPRD001)supported in part by the Collaborative Research Program of the Research Institute for Applied Mechanics,Kyushu University。
文摘A three-wave based laser polarimeter/interferometer and a CO_(2)laser dispersion interferometer are used to determine the electron and current density profiles on a Chinese fusion engineering test reactor(CFETR).Radiation shielding is designed for the combination of polarimeter/interferometer and CO_(2)dispersion interferometer.Furthermore,neutronics models of the two systems are developed based on the engineering-integrated design of CFETR polarimeter/interferometer and CO_(2)dispersion interferometer and the major material components of CFETR.The polarimeter/interferometer and CO_(2)dispersion interferometer's neutron and photon transport simulations were performed using the Monte Carlo neutral transport code to determine the energy deposition and neutron energy spectrum of the optical mirrors.The energy depositions of the first mirrors on the polarimeter/interferometer are reduced by three orders with the whole shielding.Since the mirrors of CO_(2)dispersion interferometer are very close to the diagnostic first wall,shielding space is limited and the CO_(2)dispersion interferometer energy deposition is higher than that of the polarimeter/interferometer.The dose rate after shutdown106s in the back-drawer structure has been estimated to be 83μSv h^(-1)when the radiation shield is filled in the diagnostic shielding modules,which is below the design threshold of 100μSv h^(-1).Radiation shielding design plays a key role in successfully applying polarimeter/interferometer and CO_(2)dispersive interferometer in CFETR.
基金Supported by the Project of China Academy of Engineering Physics under Grant No 2013B0103015
文摘The thick target neutron yields (TTNYs) of deuteron-induced reaction on AI and Cu isotopes are analyzed by combining the improved nuclear models and particle transport effects. The modified Glauber model is employed mainly to produce the peak of double differential cross section for the breakup process, and the exciton model and the Hauser-Feshbach theory are used for the statistical processes. The thin-layer accumulation method is used to calculate the TTNYs considering the neutron attenuation effects in the target. The calculated results are compared with the existing experimental data, and the analysis method can predict the TTNY data well at the deuteron energy of 40 MeV.