论文标题
巨型共振的理论方法
Theoretical Methods for Giant Resonances
论文作者
论文摘要
毫无疑问，随机相位近似（RPA）及其变化和扩展是描述微观理论中巨大共振的最广泛使用的工具。在本章中，我们将首先讨论RPA如何自然地出现，如果一个人在一个粒子一个孔的刺激下在基态之上具有谐波时间依赖性的状态。还将表明，RPA是``集体''状态出现的最简单方法。这些是其他教科书中出现的基本论点，但也不可避免地作为进一步讨论的起点。在本章的其余部分中，我们将重点介绍过去几十年中发生的发展：RPA的替代方案，例如有限幅度方法（FAM），最先进的计算，具有良好的能量密度功能（EDFS），以及{\ em em ab Initio}计算中的进展。我们将使用用作红色线的RPA的扩展来讨论一个粒子一个孔模型空间的各种扩大。连续体的重要性以及诸如巨型共振的衰减产品之类的独家观察力也将得到涉及。
The Random Phase Approximation (RPA) and its variations and extensions are, without any doubt, the most widely used tools to describe Giant Resonances within a microscopic theory. In this chapter, we will start by discussing how RPA comes out naturally if one seeks a state with a harmonic time dependence in the space of one particle-one hole excitations on top of the ground state. It will be also shown that RPA is the simplest approach in which a ``collective'' state emerges. These are basic arguments that appear in other textbooks but are also unavoidable as a starting point for further discussions. In the rest of the chapter, we will give emphasis to developments that have taken place in the last decades: alternatives to RPA like the Finite Amplitude Method (FAM), state-of-the-art calculations with well-established Energy Density Functionals (EDFs), and progress in {\em ab initio} calculations. We will discuss extensions of RPA using as a red thread the various enlargements of the one particle-one hole model space. The importance of the continuum, and the exclusive observables like the decay products of Giant Resonances, will be also touched upon.
