Search for a permanent electric dipole moment of mercury atoms

Experimental searches for permanent electric dipole moments (EDMs) provide extremely sensitive probes for physics beyond the standard model. The three main classes of EDM searches are: measurements on bare neutrons; measurements on paramagnetic atoms or molecules, mainly sensitive to the electron EDM; and measurements on diamagnetic atoms, mainly sensitive to CP-violating interactions between nucleons. The most sensitive diamagnetic experiment is performed on Hg-199 atoms at the University of Washington in Seattle. A four vapor-cell measurement of the Hg EDM was recently completed, resulting in an upper bound $\vert$ d(Hg) $\vert <$ 3.1x10$^{-29}$ e cm, a factor of seven improvement on the previous limit. Details on the experimental technique and results will be given, along with theoretical implications of the new limit, and prospects for improvement.