Circumstantial evidence for a non-Maxwellian plasma from femtosecond laser-matter interaction

TL;DR

This paper investigates ion acceleration in laser-generated plasmas using neutron spectroscopy, revealing evidence of non-Maxwellian plasma behavior through anisotropic neutron spectra and multiple ion collision mechanisms.

Contribution

It introduces a novel analysis of neutron spectra to identify non-Maxwellian plasma components and ion collision processes in laser-matter interactions.

Findings

Evidence of anisotropic neutron spectra indicating non-Maxwellian plasma

Identification of at least two plasma components with different acceleration mechanisms

Neutron spectra suggest collective ion acceleration in the plasma

Abstract

We study ion acceleration mechanisms in laser-plasma interactions using neutron spectroscopy. We consider different types of ion-collision mechanisms in the plasma, which cause the angular anisotropy of the observed neutron spectra. These include the collisions between an ion in the plasma and an ion in the target, and the collisions between two ions in the hot plasma. By analyzing the proton spectra, we suggest that the laser-generated plasma consists of at least two components, one of which collectively accelerated and can also produce anisotropy in the angular distribution of fusion neutrons.