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根据中子与天然核Cr及其同位素反应的总截面,去弹性散射截面和弹性散射角分布的实验数据,获得了入射中子能量从1MeV—250MeV的一组普适中子与Cr及其同位素反应的光学模型势参数.应用光学模型,扭曲波玻恩近似理论,宽度涨落修正的Hauser-Feshbach理论,和预平衡反应的激子模型,计算和分析了中子与52Cr反应的所有截面、角分布、能谱和双微分截面.理论计算与实验数据进行了分析比较. 相似文献
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根据中子与天然Zr及其同位素反应的总截面,去弹截面和弹性散射角分布的实验数据,得到一组普适的光学模型势参数;应用得到的光学模型势参数,光学模型,Hauser-Feshbach理论,预平衡反应的激子模型和扭曲波玻恩近似理论,系统计算和分析了中子与90,91,92,94Zr反应的非弹散射角分布和双微分截面,理论结果与实验很好的一致. 相似文献
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HAN Yin-Lu 《中国物理C(英文版)》2004,28(1):48-52
Based on experimental data of total, nonelastic, elastic cross section and elastic scattering angular distributions for n+Pb reactions, a set of neutron optical model potential parameters is obtained in the region of incident neutron energy from 1—300 MeV. The cross sections, angular distributions and energy spectra are calculated and analyzed by optical model, distorted wave Born approximation theory, Hauser-Feshbach theory, exciton model and cascade mechanism inside nuclear. The results indicate that the cross sections can be given for n+ 208Pb reactions which are all in good agreement with experimental data. 相似文献
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应用现有的中子与原子核Sn及其同位素反应的总截面,去弹性散射截面,弹性散射截面和弹性散射角分布的实验数据,获得一组普适的中子与Sn及其同位素反应的光学模型势参数.利用这组光学模型势参数,扭曲波玻恩近似理论,核反应Hauser-Feshbach理论和预平衡反应的激子模型,计算和分析了中子与116,118,120,122,124Sn反应分离能级的非弹性散射截面和角分布.理论计算与实验数据进行了分析比较. 相似文献
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根据中子与原子核U及其同位素反应的总截面,去弹性散射截面和弹性散射角分布的实验数据,获得了入射中子能量0.1—20MeV的一组普适中子与U及其同位素反应的光学模型势参数.应用光学模型,核裂变理论,耦合道理论,扭曲波玻恩近似理论,宽度涨落修正的Hauser-Feshbach理论和预平衡反应的激子模型,计算和分析了中子与238U反应的所有截面、角分布、能谱和双微分截面.理论计算与实验数据进行了分析比较 相似文献
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HAN Yin-Lu 《中国物理C(英文版)》2004,28(2):177-180
Based on the new measurements of total, nonelastic, elastic cross section and elastic scattering angular distributions for n+U reactions, a set of neutron optical model potential parameters is obtained in the region of incident neutron energy from 0.1 to 20 MeV. The cross sections, angular distributions, energy spectra and double differential cross sections are calculated and analyzed by optical model, nuclear fission theory, distorted wave Born approximation theory, coupled channel theory, the unified Hauser-Feshbach theory, as well as exciton model. The results indicate that our theoretical model can reasonably analysis n+ 238U reaction data with neutron energy lower than 20 MeV. 相似文献
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Polarization effect in (e, 2e) reaction process for Ar (3s) in coplanar asymmetric geometry 下载免费PDF全文
The (e, 2e) triple differential cross sections (TDCSs) of Ar (3s) are calculated by using distorted-wave Born approx- imation under coplanar asymmetric geometry. The incident electron energy is 113.5 eV, and the scattering electron angle 01 is -15~. The ejected electron energy is set at 10 eV, 7.5 eV, 5 eV, and 2 eV, respectively. The polarization effects have been discussed and the polarization potential Vpol changing from a second-order to a fourth-order term has been analyzed. Our calculated TDCSs have been compared with reported experimental and theoretical results, and the calculated TDCSs of polarization potential up to the fourth order could give a good fit with experimental results in the binary region, but fail to predict the correct recoil-to-binary ratio in most cases. 相似文献
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Theoretical Calculations of Microscopic Nuclear Reaction Data for p+209Bi in Energy Region up to 300MeV 下载免费PDF全文
ZHANG Zheng-Jun SHEN Qing-Biao HAN Yin-Lu CAI Chong-Hai SUN Xiu-Quan HOU Xun 《中国物理C(英文版)》2002,26(6):600-606
Based on nuclear reaction models, i.e., the optical model, evaporation model, exciton model and the direct reaction theory, cross sections of (p,xn) reactions and residual nuclei productions for p+209Bi reaction were calculated in energy region from threshold up to 300MeV and a set of proton optical potential parameters for 209Bi up to 500MeV were obtained. The direct inelastic cross sections were calculated with the distorted wave Born approximation theory. Theoretical results show that the direct inelastic cross sections of about 550mb are reasonable. 相似文献
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The four-body boundary corrected first Born approximation (CB1-4B) is used to calculate the single electron capture cross sections for collisions between fully stripped ions (He2+, Be4+, B5+ and C6+) and helium target at intermediate and high impact energies. The main goal of this study is to assess the usefulness of the CB1-4B method at intermediate and high impact energies for these collisions. Detailed comparisons with the measurements are carried out and the obtained theoretical cross sections are in reasonable agreement with the available experimental data. 相似文献
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在质子与48Ti,51V和52Cr反应的去弹截面、弹性散射角分布实验数据的基础上,获得了一组入射质子能量在150 MeV以下的质子与52Cr反应的光学势参数。应用光学模型、扭曲波玻恩近似理论、核内级联模型、蒸发模型、带宽度涨落修正的Hauser-Feshbach理论以及激子模型(含改进的Iwamoto–Harada模型)计算得到了质子与52Cr反应的所有截面、角分布、能谱和双微分截面。对理论计算结果与实验数据以及TENDL中的数据进行了比较分析,结果显示,理论计算结果与实验数据符合较好,且反应道截面优于TENDL的结果。 相似文献
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A. I. Nikishov 《Physics of Particles and Nuclei Letters》2009,6(6):425-432
The corrections to the leading term of the small-angle deflection of a classical particle by the Schwarzschild field and its
linear approximation were found. The corresponding cross sections were obtained. The comparison with known in Born approximation
cross sections for quantum massless particles of spins 0, 1, and 2 shows that only the leading term in all cases is the same.
As the conditions for classical treatment are well fulfilled, this means that the classical results are much more accurate
than the quantum one in Born approximation. The fact that the photon cross section is always smaller than that of massless
scalar particle (both in Born approximation) suggests that with small probability (at least of order of the difference of
these cross sections) the photon can fly by the Sun without deflection. The deflection of light, observable at a final distance
from the Sun, is also considered and it is shown that measurements at the distances of several Sun’s radii will decide which
coordinate system is the privileged one. 相似文献
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HUANG Xiao-Long 《中国物理C(英文版)》2006,30(4):306-309
Based on the experimental data of the total, the nonelastic and the elastic cross sections and the elastic scattering angular distributions for n+58Ni reactions, a set of parameters for a neutron optical model potential is obtained in the incident neutron energy region from 0.8—150MeV. Then reaction cross sections, angular distributions, energy spectra, gamma-ray production cross sections and gamma-ray production energy spectra are calculated in terms of the optical model, the distorted wave Born approximation theory, the Hauser-Feshbach theory, the exciton model and the cascade mechanism inside nuclear. The results are analyzed and compared with the existing experimental data and other evaluated data from ENBF/B-6. They are in agreement with each other within error bars. 相似文献
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Y. Zhao H.N. Xia J.B. Qi Y.S. Wang 《Journal of Quantitative Spectroscopy & Radiative Transfer》2003,77(3):301-315
A distorted-wave Born exchange (DWBE) approximation including relativistic correction is used to calculate the electron-impact ionization cross sections and rate coefficients for the highly charged ions Ar7+,…,Ar17+. The comparison of the calculated results with the experimental data and other theoretical calculations shows that the DWBE method is valid for these ions of argon. The calculated results for direct ionization cross sections and excitation autoionization were fitted by empirical formulas to meet the requirements of applications. A set of improved empirical formulas are used for the fast and accurate calculations of rate coefficients from the fit parameters of cross sections. 相似文献
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Born differential cross sections and the lowest-order radiative correction to them are obtained in the kinematics of large-angle
final photon emissions in high-energy electron-positron annihilation processes. Taking into account the possible emission
of real soft and hard photons in collinear kinematics, we show the validity of the Drell-Yan form of the differential cross
section with the nonsinglet structure functions of the initial leptons. The leading and next-to-leading contribution to the
cross sections is obtained. The relevant numerical estimations are presented.
The text was submitted by the authors in English. 相似文献
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对于能量为0.5-1MeV的入射质子,在计算中采用AuL1次壳层荧光产额的实验值代替相应的Dirac-Hartree-Slater值时,使用RPWBA-BC(经结合能和库仑歪曲修正的相对论平面波玻恩近似)电离截面计算得到的金原子LX射线相对产生截面与测量值相符。以前报道的对RPWBA-BC截面的各种修正都是不需要的 相似文献
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《中国物理C(英文版)》2015,(8)
A set of optimal proton optical potential parameters for p+184W reactions are obtained at incident proton energy up to 250 MeV.Based on these parameters,the reaction cross-sections,elastic scattering angular distributions,energy spectra and double differential cross sections of proton-induced reactions on184W are calculated and analyzed by using theoretical models which integrate the optical model,distorted Born wave approximation theory,intranuclear cascade model,exciton model,Hauser-Feshbach theory and evaporation model.The calculated results are compared with existing experimental data and good agreement is achieved. 相似文献