Equilibrium Contact Probabilities in Dense Plasmas

TL;DR

This paper uses path integral Monte Carlo calculations to determine contact probabilities in dense quantum plasmas, revealing significant many-body quantum effects that influence nuclear reaction rates and thermodynamic properties.

Contribution

It provides new quantum Monte Carlo results for contact probabilities in dense plasmas, including effects of electron screening and beyond uniform background models.

Findings

Quantum effects can change contact probabilities by an order of magnitude.

Electron screening significantly influences contact probabilities.

Thermodynamic properties of quantum OCP are analyzed.

Abstract

Nuclear reaction rates in plasmas depend on the overlap (contact) probability of the reacting ions. Path integral Monte Carlo (PIMC) calculations are used here to determine these contact probabilities, g(0), for the one component plasma (OCP) with emphasis on many-body quantum effects which can lead to order of magnitude changes. An intuitive explanation for these effects is presented. The small r behavior of g(r) for quantum systems and the relation to free energies is then derived and compared to the path integral results. Going beyond the uniform background approximation, electron screening effects and the limits of the ``constant energy shift'' approximation are discussed. Thermodynamic properties for the quantum OCP are analyzed in a final section.