Probing the dynamics of solid density micro-wire targets after ultra-intense laser irradiation using a free-electron laser

TL;DR

This study investigates the plasma dynamics of micro-wire targets post ultra-intense laser irradiation using X-ray free-electron laser measurements, revealing shock-driven surface instability and propagation inside the wire.

Contribution

It introduces a novel experimental approach combining short pulse laser and free-electron laser to probe micro-scale plasma dynamics in solid targets.

Findings

Observation of bent scattering surface indicating instability

Detection of a shock front propagating at near hole boring velocity

Evidence of surface and internal plasma dynamics post irradiation

Abstract

In this paper, we present an experiment that explores the plasma dynamics of a 7 micron diameter carbon wire after being irradiated with a near-relativistic-intensity short pulse laser. Using an X-ray Free Electron Laser pulse to measure the small angle X-ray scattering signal, we observe that the scattering surface is bent and prone to instability over tens of picoseconds. The dynamics of this process are consistent with the presence of a sharp, propagating shock front inside the wire, moving at a speed close to the hole boring velocity.