Calculation of Stark-induced absorption on the 6s6p ³P₁–6s^2 1S₀ transition in Hg

We carry out relativistic many-body calculations of the Stark-induced absorption coefficient on the 254-nm 6s6p ³P₁(F=1/2)–6s^2 1S₀ line of ¹⁹⁹Hg atom, the effect considered before by and Lamoreaux and Fortson Phys. Rev. A 46 7053 (1992)] using a simple central field estimate. The Stark-induced admixing of states of opposite parity opens additional M1 and E2 transition channels. We find that the resulting M1-E1 absorption dominates over E2-E1 absorption. The value of the E2-E1 absorption coefficient depends strongly on the details of treatment of the correlation problem. As a result, our numerical values differ substantially from those of the earlier central field calculation. Reliable calculation of this effect can enable a useful experimental check on the optical technique being used to search for a permanent electric-dipole moment of the ¹⁹⁹Hg atom.