Particle-in-Cell Modeling of Laser Thomson Scattering in Low-Density Plasmas at Elevated Laser Intensities

TL;DR

This paper develops and validates a Particle-in-Cell model to understand how high-intensity lasers perturb low-density plasmas during Thomson scattering measurements, ensuring more accurate plasma diagnostics.

Contribution

The paper introduces a kinetic simulation model that captures laser-induced perturbations in plasma density during Thomson scattering at elevated laser intensities.

Findings

Laser intensity can significantly perturb plasma density.

The Particle-in-Cell model accurately predicts these perturbations.

Results help improve plasma density measurements in high-intensity regimes.

Abstract

Incoherent Thomson scattering is a non-intrusive technique commonly used for measuring local plasma density. Within low-density, low-temperature plasma's and for sufficient laser intensity, the laser may perturb the local electron density via the ponderomotive force, causing the diagnostic to become intrusive and leading to erroneous results. A theoretical model for this effect is validated numerically via kinetic simulations of a quasi-neutral plasma using the Particle-in-Cell technique.