QEDMOD: Fortran program for calculating the model Lamb-shift operator

Abstract

We present Fortran package QEDMOD for computing the model QED operator hQED that can be used to account for the Lamb shift in accurate atomic-structure calculations. The package routines calculate the matrix elements of hQED with the user-specified one-electron wave functions. The operator can be used to calculate Lamb shift in many-electron atomic systems with a typical accuracy of few percent, either by evaluating the matrix element of hQED with the many-electron wave function, or by adding hQED to the Dirac–Coulomb–Breit Hamiltonian. New version program summaryProgram Title: QEDMODProgram Files doi:http://dx.doi.org/10.17632/ct869v4gxn.1Licensing provisions: Apache License 2.0.Programming language: Fortran 77.Journal reference of previous version: Computer Physics Communications 189 (2015) 175-181, http://dx.doi.org/10.1016/j.cpc.2014.12.002.Does the new version supersede the previous version?: Yes.Nature of problem: Fortran code for computation of the model QED operator that approximates the Lamb shift in many-electron atoms.Solution method: The method of solution is based on the algorithm developed in Ref. [1].Reasons for the new version: Extension of the region of applicability; fixing of minor bugs.Summary of revisions: Region of supported nuclear charges is extended to Z∈[3,120]; a problem that appeared for the extended nuclear model for several selected values of Z is fixed. [1]V. M. Shabaev, I. I. Tupitsyn, and V. A. Yerokhin, Model operator approach to the Lamb shift calculations in relativistic many-electron atoms, Phys. Rev. A 88, 012513 (2013).