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arXiv · 1511.05753

Calculations on the stopping power of a heterogeneous Warm Dense Matter

Abstract

The stopping power of Warm Dense Matter (WDM) is estimated by means of the individual contributions of free electrons and bound electrons existing in this special kind of matter, located between classical and degenerate plasmas. For free electrons, the dielectric formalism, well described in our studies, is used to estimate the free electron stopping power. For bound electrons, the mean excitation energy of ions is used. Excitation energies are obtained through atomic calculations of the whole atom or, shell by shell in order to estimate their stopping power. Influence of temperature and density is analyzed in case of an impinging projectile. This influence becomes important for low projectile velocities and is negligible for high ones. Using free and bound electron analysis, the stopping power of an extended WDM is inferred from a dynamical calculation of energy transferred from the projectile to the plasma, where the Bragg peak and stopping range are calculated. Finally, this theoretical framework is used to study a typical plasma density profile of a WDM heated by lasers.

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David Casas, Alexander A. Andreev, Matthias Schnürer, Manuel D. Barriga-Carrasco, Roberto Morales, Luis González-Gallego. 2015-12-01. Calculations on the stopping power of a heterogeneous Warm Dense Matter. https://doi.org/10.1017/s0263034616000161

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