论文标题
（n，γ）对中子核的（N，γ）反应的连续性随机相近似：集体效应和共振
Continuum random-phase approximation for (n,γ) reactions on neutron-rich nuclei: collective effects and resonances
论文作者
论文摘要
我们制定了一种微观理论，以计算使用连续的随机相近似（CRPA）对时间依赖性密度功能理论（TDDFT）的连续性随机相近似（CRPA）计算辐射中子捕获反应的横截面。通过将统计反应模型可能不合适的R-PROCESS应用于R-Process的意义，我们通过CRPA-TDDDFT的单个多体框架来描述入射中子的初始状态与伽马衰减的最终状态之间的过渡。通过CRPA方法，可以描述$（N，γ）$反应中存在的各种激发模式，包括软偶极式激发，巨大的共振以及非散热激发和单粒子共振。此外，它使我们能够描述$（n，γ）$的反应，其中伽马过渡的最终状态是低洼的表面振动状态。我们通过对反应$ ^{139} {\ rm sn}（n，γ） ^{140} {\ rm sn} $执行数值计算来演示理论。我们讨论超出单粒子模型的各种新功能。狭窄和广泛的共振源于非散型四极杆和八极振动状态的非综合和集体激发以及作用。
We formulate a microscopic theory to calculate cross section of the radiative neutron capture reaction on neutron-rich nuclei using the continuum random-phase approximation (cRPA) to the time-dependent density functional theory (TDDFT). With an intension of applying to the r-process, for which the statistical reaction model may not be appropriate, we describe the transition between a initial state of incident neutron and a final state of the gamma decay by means of a single many-body framework of the cRPA-TDDFT. With the cRPA approach, it is possible to describe various excitation modes present in the $(n,γ)$ reaction, including soft dipole excitation, the giant resonances as well as non-collective excitations and the single-particle resonances. Furthermore, it enables us to describe the $(n,γ)$ reaction where the final states of the gamma transition are low-lying surface vibrational states. We demonstrate the theory by performing numerical calculation for the reaction $^{139}{\rm Sn} (n,γ) ^{140}{\rm Sn}$. We discuss various new features which are beyond the single-particle model; presence of narrow and wide resonances originating from non-collective and collective excitations and roles of low-lying quadrupole and octupole vibrational states.
