We present a systematic study of 6Li elastic scattering and total reaction cross sections at incident energies around the Coulomb barrier within the continuum discretized coupled-channels(CDCC)framework,where 6Li is t...We present a systematic study of 6Li elastic scattering and total reaction cross sections at incident energies around the Coulomb barrier within the continuum discretized coupled-channels(CDCC)framework,where 6Li is treated in anα+d two-body model.Collisions with 27Al,64Zn,138Ba,and 208Pa are analyzed.The microscopic optical potentials(MOP)based on Skyrme nucleon-nucleon interaction forαand d are adopted in CDCC calculations and satisfactory agreement with the experimental data is obtained without any adjustment on MOPs.For comparison,αand d global phenomenological optical potentials(GOP)are also used in CDCC analysis and a reduction of no less than 50%on the surface imaginary part of deuteron GOP is required for describing the data.In all cases,the 6Li breakup effect is significant and provides repulsive correction to the folding model potential.The reduction on the surface imaginary part of GOP of deuteron reveals a strong suppression of the reaction probability of deuteron as a component of 6Li when compared with that of a free deuteron.Further investigation is performed by considering the d breakup process equivalently within the dynamic polarization potential approach,and the results show that d behaves in a manner similar to a tightly bound nucleus in 6Li induced reactions.展开更多
The cross sections of the^(169)Tm(n,2n)^(168)Tm reaction have been measured at incident energies of 12 to 19.8 MeV using the activation technique,relative to the^(93)Nb(n,2n)^(92)mNb reaction.Thulium(Tm)samples were i...The cross sections of the^(169)Tm(n,2n)^(168)Tm reaction have been measured at incident energies of 12 to 19.8 MeV using the activation technique,relative to the^(93)Nb(n,2n)^(92)mNb reaction.Thulium(Tm)samples were irradiated on the surface of a two-ring orientation assembly with neutrons produced from the^(3)H(d,n)^(4)He reaction at the 5SDH-21.7-MV Tandem accelerator in China.Theoretical model calculations were performed.The present data were then compared with previous experimental data and available evaluated data.This study provides more precise nuclear data for improvement of future evaluations.展开更多
基金Supported by the National Natural Science Foundation of China(U2067205)。
文摘We present a systematic study of 6Li elastic scattering and total reaction cross sections at incident energies around the Coulomb barrier within the continuum discretized coupled-channels(CDCC)framework,where 6Li is treated in anα+d two-body model.Collisions with 27Al,64Zn,138Ba,and 208Pa are analyzed.The microscopic optical potentials(MOP)based on Skyrme nucleon-nucleon interaction forαand d are adopted in CDCC calculations and satisfactory agreement with the experimental data is obtained without any adjustment on MOPs.For comparison,αand d global phenomenological optical potentials(GOP)are also used in CDCC analysis and a reduction of no less than 50%on the surface imaginary part of deuteron GOP is required for describing the data.In all cases,the 6Li breakup effect is significant and provides repulsive correction to the folding model potential.The reduction on the surface imaginary part of GOP of deuteron reveals a strong suppression of the reaction probability of deuteron as a component of 6Li when compared with that of a free deuteron.Further investigation is performed by considering the d breakup process equivalently within the dynamic polarization potential approach,and the results show that d behaves in a manner similar to a tightly bound nucleus in 6Li induced reactions.
基金Supported by the National Natural Science Foundation of China(12075216)。
文摘The cross sections of the^(169)Tm(n,2n)^(168)Tm reaction have been measured at incident energies of 12 to 19.8 MeV using the activation technique,relative to the^(93)Nb(n,2n)^(92)mNb reaction.Thulium(Tm)samples were irradiated on the surface of a two-ring orientation assembly with neutrons produced from the^(3)H(d,n)^(4)He reaction at the 5SDH-21.7-MV Tandem accelerator in China.Theoretical model calculations were performed.The present data were then compared with previous experimental data and available evaluated data.This study provides more precise nuclear data for improvement of future evaluations.
基金supported by Guizhou Provincial Science and Technology Foundation,China(No.[2019]1229)the National Natural Science Foundation of China(Nos.21361007,51776046)。
文摘通过高温固相技术合成Ho^(3+)和Yb^(3+)共掺杂La_(7)P_(3)O_(18)上转换荧光粉。XRD结果表明,合成样品是空间群为P21/n的单斜结构的La_(7)P_(3)O_(18)晶体和少量La PO4晶体的混合物。紫外可见漫反射光谱结果证实La_(7)P_(3)O_(18)晶体是一种光学带隙为4.10 e V的间接半导体。经980 nm激光激发,Ho^(3+)和Yb^(3+)共掺杂La_(7)P_(3)O_(18)荧光粉发射出Ho^(3+)离子特征的蓝色(486 nm)、绿色(550 nm)和红色(661 nm)特征峰,其中,661 nm处发射峰在样品上转换发光光谱中占主导地位。此外,随着Ho^(3+)和Yb^(3+)掺杂量的增加,样品上转换发光强度先增大后减小。当Ho^(3+)和Yb^(3+)的掺杂量分别达到1%和10%(摩尔分数)时,样品出现浓度猝灭现象,其机制为电四极-电四极相互作用。泵浦功率和发光强度关系表明,样品的绿光和红光发射均源于双光子吸收过程激发。Ho^(3+)和Yb^(3+)共掺杂La_(7)P_(3)O_(18)晶体上转换发光色坐标位于橙红色区域。
