Nuclear Magnetic and Gamow-Teller Transitions

核磁和伽莫夫跃迁

• 批准号: 60540168
• 负责人: SHIMIZU Kiyotaka
• 金额: $ 1.02万
• 依托单位: University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-60540168/
• 关键词: Magnetic transition; Gamow; Teller transition; Tensor correlation; Meson exchange currents; Spin-isospin resporse; Coulomb sumrule; 二粒子・二空孔励起; 連続状態RPA; クォーク交換流; 相対論的効果

Study of the nuclear magnetic moments and beta-decay played a very important role in studying nuclear structure and effeetive interactions. Resently a lot of information about magnetic and Gamow-Teller transitions observed in proton and electron scatterings, londitudinal and transverse responses in the quasi-elastic electron scalterings etc. has been obtained. We have studied the effects of core polarization, especially tensor correlations, meson exchange currents, <DELTA>-hole excitations and quark degrees of freedom on the above reactions. In the magnetic and Gamow-teller transitions, it has been known that the transition strengths have been distributed over the high energy excitation regions experimentally. It was, however, very difficult to clarify the mechanism of the distribution theoretically. We have developed the extended modified Rondom Phase Approximation which takes into account the effect of grount state corretlations and exchange currents.We have also studied the spin-isospin response in the quasi-elastic region. Here the continuum RPA theory has been employed. The method how to include the exchange term has been newly developed. We have obtained the results which are different from other calculations in nuclear matter. We have also applied the continuum RPA with exchange terms on the coulomb sum rule in the electron scattering.

核磁矩和β衰变的研究在研究原子核结构和有效相互作用中起着非常重要的作用。最近，在质子和电子散射中观察到的磁跃迁和Gamow-Teller跃迁，在准弹性电子标度中的纵向和横向响应等方面都得到了大量的信息。我们研究了核极化，特别是张量关联、介子交换电流、-lt；Delta&gt；空穴激发和夸克自由度对上述反应的影响。在磁跃迁和Gamow-Teller跃迁中，已知跃迁强度分布在高能激发区。然而，从理论上澄清这种分配的机制是非常困难的。我们发展了扩展的修正随机位相近似，它考虑了基态关联和交换电流的影响，并研究了准弹性区域的自旋-同位旋响应。这里采用了连续介质RPA理论。如何包含交换术语的方法是新开发的。我们得到了与其他核物质计算不同的结果。我们还将具有交换项的连续介质RPA应用于电子散射中的库仑和规则。

项目成果

S.Takeuchi: Physics Letters B. 179. 197-200 (1986)

S.Takeuchi：物理快报 B. 179. 197-200 (1986)

Zhang Zong-Ye: Nuclear Physics A. 443. 557-569 (1985)

张宗业：核物理A. 443. 557-569 (1985)

A.Arima: "Isoscalar Magretic Moments and the Role of the <DELTA>-hole Excitation" Hyperfine Interactions. 21. 79-83 (1985)

A.Arima：“等标量磁矩和 <DELTA> 空穴激发的作用”超精细相互作用。

T. Cheon: "Medium Corrections Intermediate Energy Nucleon-Nucleios Scattering" Nuclear Physics A. 445. 227-244 (1985)

T. Cheon：“中等修正中能核子-核子散射”核物理 A. 445. 227-244 (1985)

Zhang Zong-Ye: "Influence of Six-Quark Bags on the NN Interaction in a Resonating Group Scattering Calculation" Nuclear Physics A. 443. 557-569 (1985)

张宗业：“六夸克袋对共振群散射计算中神经网络相互作用的影响”核物理 A. 443. 557-569 (1985)