共查询到19条相似文献,搜索用时 46 毫秒
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本文计算了μ介子在He3核上俘获的几率、末态H3核的角分布和极化。所采用的理论是带有重正化效应(包含弱磁矩及赝标项)的V-A普适弱作用理论。在计算中考虑了μ和He3核在始态有极化及处于不同超精细态上的情况。在计算中假定了He3核的基态是纯S态,这时忽略了由张量力以及其他自旋轨道耦合力引起的其他态。介子交换电流的效应也没有考虑。在以上这两个假定下,我们证明了俘获几率中只包含一个未知的原子核矩阵元,这个矩阵元恰好是原子核密度函数的富氏分量。利用μ介子(或电子)与He3(或H3)原子核的散射可以确定这个未知矩阵元。 相似文献
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利用多体场论方法,本文对μ-在原子核上的俘获作了系统研究.在没有任何可调参数的情况下,对于从轻核到重核各种原子核上的μ-俘获率作了计算.发现,自旋-同位旋相关的强作用的重整化效应及μ-在原子核上的束缚能效应是透彻理解这种弱作用过程的关键. 相似文献
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本文计算了μ介子在He~3核上俘获的几率、末态H~3核的角分布和极化。所采用的理论是带有重正化效应(包含弱磁矩及赝标项)的V-A普适弱作用理论。在计算中考虑了μ和He~3核在始态有极化及处于不同超精细态上的情况。在计算中假定了He~3核的基态是纯S态,这时忽略了由张量力以及其他自旋轨道耦合力引起的其他态。介子交换电流的效应也没有考虑。在以上这两个假定下,我们证明了俘获几率中只包含一个未知的原子核矩阵元,这个矩阵元恰好是原子核密度函数的富氏分量。利用μ介子(或电子)与He~3(或H~3)原子核的散射可以确定这个未知矩阵元。 相似文献
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本文计算了μ-介子和原子核Li6在不同超精细结构状态上,μ-+Li6→He6+ν的跃迁几率。指出在5%的误差范围以内,在两种超精细结构状态上俘获几率的比值和原子核矩阵元无关。 相似文献
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用三种不同的核波函数计算了u-介子在He3核上的俘获几率,将结果与其他作者的结果进行了比较。 相似文献
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The energies, shifts, widths, and radiative rates of double excited Be+ resonances are calculated using the saddle point and saddle-point complex-rotation methods. A restricted variational method is used to extrapolate a better nonrelativistic energy. Relativistic effects are included using first-order perturbation theory. These results are used to make a better understanding of observed Be+ spectra. 相似文献
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The photoionization cross-section of Be2+ has been measured in the range from threshold at 154 eV up to 420 eV. The value at threshold of [1.4 ± 0.2] × 10?18 cm2 is in good agreement with theoretical predictions. The method used was that of absorption using two laser produced plasmas. The doubly excited resonance 2s2p 1p0 at 281.25 ± 0.07 eV has been observed and its Fano profile measured. 相似文献
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经典轨迹蒙特卡罗(CTMC)方法是研究离子-原子碰撞系统电荷交换过程的常用方法,广泛应用于天体物理以及实验室等离子体环境下重粒子碰撞过程的研究.本文利用四体碰撞模型(4-CTMC)研究了包括两个束缚电子的四体碰撞过程,通过数值求解四体碰撞系统的哈密顿运动方程,计算了高电荷态入射离子(Li3+,Be4+和O7+)同氦原子在大能量范围的单、双电子电离和俘获截面.H++He碰撞截面的计算中,在50—200 keV/amu的入射能区,4-CTMC的结果几乎重复了实验结果.在高电荷态入射情形下,4-CTMC计算的单电子电离和俘获截面值相较于三体碰撞模型(3-CTMC)在100—500 keV/amu的入射能区内与实验符合更好.尽管4-CTMC和3-CTMC忽略了电子关联,均高估了双电子电离和俘获截面(与实验值相比),但4-CTMC的结果更接近实验. 相似文献
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In this paper, the radiative capture in the inelastic channel of the compound nucleus is discussed.
Starting from the S-matrix theory, the calculation formular for this situation is derived. Then connected with the optical model and Hauser-Feshbach's statistical theory with the width fluctuation correction, a formular convenient for calculations is given.
Making use of the formular obtained above, the numerical calculations are made for the average cross-section of 51V and other nuclei, and the comparison with the statistical (n, γ) and (n, n′) cross sections is made.
The results show that if the incident energies of the neutron are large enough to open the inelastic channel, the cross sections of this process will have the same order of magnitude as the statistical cross sections. Hence it is an important mechanism in the (n, γ) reactions. 相似文献
Starting from the S-matrix theory, the calculation formular for this situation is derived. Then connected with the optical model and Hauser-Feshbach's statistical theory with the width fluctuation correction, a formular convenient for calculations is given.
Making use of the formular obtained above, the numerical calculations are made for the average cross-section of 51V and other nuclei, and the comparison with the statistical (n, γ) and (n, n′) cross sections is made.
The results show that if the incident energies of the neutron are large enough to open the inelastic channel, the cross sections of this process will have the same order of magnitude as the statistical cross sections. Hence it is an important mechanism in the (n, γ) reactions. 相似文献
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考虑原子核理论中超导效应对gR因子的影响,在给出偶核gR因子在推转模型(cranking model)基础上的计算公式之后,利用Nilsson波函数计算了62Sm152核的gR因子。计算结果与实验值符合很好,反映了原子核超导理论的正确性。 相似文献
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