Investigating Mechanisms of State Localization in Highly-Ionized Dense Plasmas

TL;DR

This paper reports the first experimental observation of K$_{eta}$ emission from highly charged Mg ions in dense plasma, revealing state relocalization effects and validating theoretical models with first-principles calculations.

Contribution

It provides the first experimental evidence of state relocalization in dense plasmas and combines this with first-principles theoretical analysis.

Findings

Observation of K$_{eta}$ emission from highly charged Mg ions.

State relocalization occurs at high charge states in dense plasmas.

Theoretical results agree well with experimental data.

Abstract

We present the first experimental observation of K$_{\beta}$ emission from highly charged Mg ions at solid density, driven by intense x-rays from a free electron laser. The presence of K$_{\beta}$ emission indicates the $n=3$ atomic shell is relocalized for high charge states, providing an upper constraint on the depression of the ionization potential. We explore the process of state relocalization in dense plasmas from first principles using finite-temperature density functional theory alongside a wavefunction localization metric, and find excellent agreement with experimental results.