Scaling laws for plasma production and pellet acceleration by laser

Abstract

The results from a spherical-symmetry hydrodynamic calculation are adapted to describe the production of large plasmas by the laser ablation of solid-density pellets. Expressions are given for the rate of ablation, plasma temperature and ion energy. The upper limit on the ionized particle number is set by pellet disintegration following heating by laser-driven shock. Scaling laws are derived for the total plasma energy and particle number. Plasma conductivity transforms one-sided illumination into an approximately spherical ablation, allowing a discussion of the scaling laws for laser-induced acceleration. The reduction in laser acceleration due to quasi-spherical ablation has negative implications for laser acceleration as a method of reactor re-fuelling.