Second-order effects on the hyperfine structure of P states of alkali-metal atoms

We analyze second-order M1-M1 and M1-E2 effects on the hyperfine structure (HFS) of the lowest-energy P states of alkali-metal atoms arising from the coupling of the two (J = 1/2, 3/2) fine-structure levels through the hyperfine interaction. We find these effects to be especially sizable in Li, leading to a 9 sigma correction to the most accurate reported experimental value of the A(P-1/2) HFS constant of 7Li [Das and Natarajan, J. Phys. B 41, 035001 (2008)]. For the remaining alkali-metal systems, the results tabulated within may be referenced as higher precision is sought in experimental determination of the HFS constants.