Time-reversal-violating Schiff moment ofHg199

We calculate the Schiff moment of the nucleus ${}^{199}\mathrm{Hg}$, created by πNN vertices that are odd under parity (P) and time-reversal (T). Our approach, formulated in diagrammatic perturbation theory with important core-polarization diagrams summed to all orders, gives a close approximation to the expectation value of the Schiff operator in the odd-A Hartree-Fock-Bogoliubov ground state generated by a Skyrme interaction and a weak P- and T-odd pion-exchange potential. To assess the uncertainty in the results, we carry out the calculation with several Skyrme interactions, the quality of which we test by checking predictions for the isoscalar-$E1$ strength distribution in ${}^{208}\mathrm{Pb}$, and estimate most of the important diagrams we omit.