Reexamining Black-Body Shifts for Hydrogenlike Ions

TL;DR

This paper analyzes how black-body radiation affects energy levels and stability in hydrogen-like ions, revealing charge-dependent shifts and decay widths that impact high-precision atomic experiments.

Contribution

It provides a detailed examination of black-body induced energy shifts and decay widths in hydrogen-like ions, highlighting their dependence on nuclear charge and implications for atomic stability.

Findings

Black-body shifts increase with the square of nuclear charge.

Black-body shifts due to virtual transitions decrease with the fourth power of nuclear charge.

Black-body interactions induce a finite decay width in atomic hydrogen's ground state.

Abstract

We investigate black-body induced energy shifts for low-lying levels of atomic systems, with a special emphasis on transitions used in current and planned high-precision experiments on atomic hydrogen and ionized helium. Fine-structure and Lamb-shift induced black-body shifts are found to increase with the square of the nuclear charge number, whereas black-body shifts due to virtual transitions decrease with increasing nuclear charge as the fourth power of the nuclear charge. We also investigate the decay width acquired by the ground state of atomic hydrogen, due to interaction with black-body photons. The corresponding width is due to an instability against excitation to higher excited atomic levels, and due to black-body induced ionization. These effects limit the lifetime of even the most fundamental, a priori absolutely stable, "asymptotic" state of atomic theory, namely the ground state of atomic hydrogen.