Numerical modeling of laser-driven ion acceleration from near-critical gas targets

TL;DR

This paper uses Particle-In-Cell simulations to investigate how near-critical gas target density affects laser-driven ion acceleration, revealing that higher densities enhance ion energy and influence electron distribution.

Contribution

It provides detailed simulation analysis of ion and electron acceleration mechanisms in near-critical gas targets under ultra high intensity laser interaction.

Findings

Higher gas jet density increases peak ion energy.

Increased density broadens electron angular distribution.

Gas density significantly influences ion spectrum features.

Abstract

In the past two decades, laser-accelerated ion sources and their applications have been intensely researched. Recently, it has been shown through experiments that proton beams with characteristics comparable to those obtained with solid targets can be obtained from gaseous targets. By means of Particle-In-Cell simulations, this paper studies in detail the effects of a near-critical density gradient on ion and electron acceleration after the interaction with ultra high intensity lasers. We can observe that the peak density of the gas jet has a significant influence on the spectrum features. As the gas jet density increases, so does the peak energy of the central quasi-monoenergetic ion bunch due to the increase in laser absorption while at the same time having a broadening effect on the electron angular distribution.