Radiative-nonrecoil corrections of order alpha^2 (Z alpha)^5 to the Lamb shift

TL;DR

This paper calculates high-order quantum electrodynamics corrections to the Lamb shift, confirming previous results and enhancing their precision through analytical and numerical methods.

Contribution

It provides detailed calculations of order alpha^2 (Z alpha)^5 corrections to the Lamb shift, including master integrals, using dimensional regularization and a covariant gauge.

Findings

Confirmed previous results for the corrections

Improved the precision of the correction values

Provided new values for 32 master integrals

Abstract

We present results for the corrections of order alpha^2 (Z alpha)^5 to the Lamb shift. We compute all the contributing Feynman diagrams in dimensional regularization and a general covariant gauge using a mixture of analytical and numerical methods. We confirm results obtained by other groups and improve their precision. Values of the 32 master integrals for this and similar problems are provided.