(Institute of Physics, 2010) Campbell, Wesley; DeMille, David; Vultha, Amar; Gurevich, Yulia Vsevolodovna; Hutzler, Nicholas; Parsons, Maxwell Fredrick; Patterson, David; West, Elizabeth Petrik; Spaun, Ben; Gabrielse, Gerald; Doyle, John
The electric dipole moment of the electron (eEDM) is a signature of CP-violating physics beyond the Standard Model. We describe an ongoing experiment to measure or set improved limits to the eEDM, using a cold beam of thorium monoxide (ThO) molecules. The metastable (H) (^{3})(\Delta)(_{ 1}) state in ThO has important advantages for such an experiment. We argue that the statistical uncertainty of an eEDM measurement could be improved by as much as 3 orders of magnitude compared to the current experimental limit, in a first-generation apparatus using a cold ThO beam. We describe our measurements of the (H) state lifetime and the production of ThO molecules in a beam, which provide crucial data for the eEDM sensitivity estimate. ThO also has ideal properties for the rejection of a number of known systematic errors; these properties and their implications are described.
