Finite-nuclear-size effect for hydrogenlike ions under high external pressure

TL;DR

This study examines how high external pressure affects finite-nuclear-size corrections and electron-capture decay rates in hydrogenlike ions confined within a spherical cavity.

Contribution

It introduces a numerical approach to analyze pressure-induced changes in atomic energy levels and decay rates considering nuclear size effects.

Findings

FNS corrections increase with pressure in confined ions.

Electron-capture decay rates are markedly enhanced under pressure.

Pressure lifts degeneracies and modifies FNS effects across states.

Abstract

The influence of pressure on finite-nuclear-size corrections to atomic energy levels and electron-capture decay rate is investigated in confined hydrogenlike ions. The ions are modeled inside an impenetrable spherical cavity, with a Gaussian distribution used to represent the nuclear charge distribution. For each confinement radius used to simulate external pressure, the energies and wave functions of the lowest-lying bound states are determined by numerically solving the Dirac equation via the kinetically balanced generalized pseudospectral method. In contrast to unconfined ions, both the FNS corrections and electron-capture decay rates increase markedly under pressure and exhibit parallel trends with increasing confinement. Pressure also removes level degeneracies and alters the relative magnitudes of FNS corrections across different bound states. Moreover, the nuclear charge radius is found to significantly affect the pressure-enhanced electron-capture decay rate.