Plasma Diagnostics Using K-Line Emission Profiles of Argon

TL;DR

This paper uses K-line emission profiles from argon plasmas created by high-energy lasers to diagnose plasma temperature gradients and ionization states, employing ab initio calculations and comparing results with existing models.

Contribution

It introduces a quantum statistical approach that accounts for plasma effects on emission energies, providing improved plasma diagnostics over traditional models.

Findings

Successful reproduction of spectral features influenced by ionization and excitation.

Identification of temperature gradients within argon droplets from 10 eV to 170 eV.

Differences in temperature distribution results compared to the FLYCHK code.

Abstract

K-line profiles emitted from a warm dense plasma environment are used for diagnostics of Ar droplet plasmas created by high energy laser pulses. We observe temperature gradients within the Ar droplet from cold temperatures of the order of some 10 eV up to higher temperatures of about 170 eV. Non-perturbative wave functions are calculated as well as ionization energies, binding energies and relevant emission energies using a chemical {\it ab initio} code. The plasma screening is considered within a perturbative approach to the Hamiltonian. The plasma effect influences the many-particle system resulting in energy shifts due to electron-ion and electron-electron interaction. With this approach we get a good reproduction of spectral features that are strongly influenced by ionization and excitation processes within the plasma. Comparing with the widely known FLYCHK code, counting for internal degrees of freedom (bound states) and treating pressure ionization within our quantum statistical approach leads to different results for the inferred temperature distribution.