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arXiv · 2412.05317

Electron-impact ionization of Si IV-VIII relevant for inertial confinement fusion

Jean-Christophe Pain·Djamel Benredjem
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Abstract

In this work, we investigate the ionization of silicon by electron impacts in hot plasmas. Our calculations of the cross sections and rates rely on the Coulomb-Born-Exchange, Binary-Encounter-Dipole and Distorted-Wave methods implemented in the Flexible Atomic Code (FAC), and are compared with measurements and other theoretical values. We use a semi-empirical formula for the cross section, which involves a small set of adjustable parameters. Configuration interaction is taken into account and is shown to affect the cross section at low energy, in particular for Si$^{3+}$. The rate coefficient is then expressed in terms of these parameters and is represented in a large temperature interval, up to 10$^8$ K. As expected, the agreement with measurements improves for increasing ion charges, confirming the applicability of our approach to hot plasma studies such as inertial-confinement fusion, and its reliability.

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Jean-Christophe Pain, Djamel Benredjem. 2024-12-02. Electron-impact ionization of Si IV-VIII relevant for inertial confinement fusion. https://arxiv.org/abs/2412.05317

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