Observability of Rearrangement Energies and Relaxation Times

Abstract

We present a clarification of the often misunderstood concept of rearrangement that affects particle removal from finite fermion systems. A separation energy is defined which depends on the speed of removal as a result of physical rearrangement processes. It is shown how single-particle eigenvalues can be observed when a single-particle description applies to the many-body system. Calculations of atomic rearrangement energies are discussed, and a linear $Z$ dependence is derived. The photo-ionization spectrum for $1s$ electrons from Ne is used as a quantitative example to extract rearrangement energy and time. Possible application to nucleon-removal data analysis is discussed.