Hyperfine Contact Interaction in the Iron Atom Calculated by Many-Body Theory

Abstract

The contribution of the hyperfine contact interaction in the iron atom has been calculated by many-body theory. Terms involving one and two Coulomb interactions have been included, and our result for the contact constant is -4.55 MHz as compared with the experimental result of -5.1 MHz obtained by Childs and Goodman. Inclusion of an approximate relativistic correction changes the calculated value to -4.87 MHz. An estimate of higher-order terms gives a theoretical result -5.35 MHz or -5.72 MHz when the relativistic correction factor is included.