Modeling stopping power of ions in plasmas using parametric potentials

Abstract

We present a study of the ion stopping power due to free and bound electrons in a warm dense plasma. Our main goal is to propose a method of stopping-power calculation expected to be valid for any ionization degree. The free-electron contribution is described by the Maynard-Deutsch-Zimmerman formula and the bound-electron one relies on the Bethe formula with corrections, in particular taking into account density and shell effects. The impact of the bound-state computation by three different parametric potentials is investigated within the Garbet formalism for the mean excitation energy. The first parametric potential is due to Green, Sellin and Zachor, the second one was proposed by Yunta, and the third one was introduced by Klapisch in the framework of atomic-structure computations. The results are compared to the ones of self-consistent average-atom calculations. This approach correctly bridges the limits of neutral and fully-ionized matter.