Microscopic optical-model calculations of neutron total cross sections and cross section differences.
Microscopic optical-model calculations of neutron total cross sections and cross section differences.
复制标题
中子总截面和截面差的微观光学模型计算。
DOI：
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发表时间：
1989
期刊：
影响因子：
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通讯作者：
Phillips
中科院分区：
文献类型：
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作者：
Camarda;Dietrich;Phillips
利用Jeukenne，Lejeune和Mahaux的微观光学模型，计算了6char21{60 MeV的绝对中子总截面和绝对截面差，并与实验数据进行了比较。除了${142}MATHEM{Ce}$外，在质子密度为${EnsureMate{
由${ensureath{u}}^{mathm{ensureath{-}数据和由关系${susureath{
Ho}}_{n}$=(N/Z)${保证数学{
Ho}}_{p}$，这意味着确保数学{Delta}${r}_{mathrm{np}}$=<${r}_{n}^{2}$${>}^{1/2}$-<${r}_{p}^{2}${>}^{1/2}$=0。通过选择${ensureath{}，获得了与$^{142}主{ce}$数据的满意一致性
在确保数学{Delta}${r}_{mathm{Np}}$=0.05Fm的情况下，$^{142}mathm{ce}$获得$^{142}mathm{ce}$，并且$^{142}mathm{ce}$虚势的强度增加10%。在尝试拟合$^{44}mathm{Ca}$数据时，对$^{44}mathm{Ca}$进行了类似的选择，以确保数学{Delta}${r}_{mathm{np}}$和想象的势强度。以前对这一数据进行的唯象分析与我们的结果是定性一致的，这表明，在具有闭合中子壳的核中加入少量中子，与其闭合壳层同位素相比，产生的核具有略厚的中子皮和更大的中子反应截面。
Using the microscopic optical model of Jeukenne, Lejeune, and Mahaux we have calculated the absolute neutron total cross sections and cross section differences of $^{140}mathrm{Ce}$, $^{139}mathrm{Ce}$, $^{141}mathrm{Ce}$, $^{142}mathrm{Ce}$, and $^{40}mathrm{Ca}$, $^{44}mathrm{Ca}$ from 6char21{}60 MeV and have made comparisons with experimental data. Except for $^{142}mathrm{Ce}$, reasonable agreement with the mass 140 data was achieved with proton densities ${ensuremath{
ho}}_{p}$ of the nuclei determined by ${ensuremath{mu}}^{mathrm{ensuremath{-}}}$ data and neutron densities determined by the relationship ${ensuremath{
ho}}_{n}$=(N/Z)${ensuremath{
ho}}_{p}$ which implies ensuremath{Delta}${r}_{mathrm{np}}$ =〈${r}_{n}^{2}$${〉}^{1/2}$ -〈${r}_{p}^{2}$${〉}^{1/2}$=0. Satisfactory agreement with the $^{142}mathrm{Ce}$ data was obtained by choosing a ${ensuremath{
ho}}_{n}$ for $^{142}mathrm{Ce}$ with ensuremath{Delta}${r}_{mathrm{np}}$=0.05 fm and by a 10% increase in the strength of the $^{142}mathrm{Ce}$ imaginary potential. Similar choices of ensuremath{Delta}${r}_{mathrm{np}}$ and imaginary potential strength were made for $^{44}mathrm{Ca}$ in trying to fit the $^{44}mathrm{Ca}$ data. Previous phenomenological analyses carried out for this data are in qualitative agreement with our results, which imply that the addition of a few neutrons to a nucleus with a closed neutron shell yields a nucleus with a slightly thicker neutron skin and a larger neutron reaction cross section when compared to their closed shell isotopes.