PHYSICS of EDM

The EDM experiment will search for an Electric Dipole Moment (EDM) of the neutron. An EDM violates Time-Reversal Invariance (as well as CP - Charge Conjugation-Parity - assuming CPT invariance) and is expected to be very small in the standard model (< 10**-31 e-cm). In fact the standard model apparently does not provide enough CP violation to explain the matter-antimatter asymmetry in the Universe. One solution to this dilemma is a "large" CP violation in the neutron, eg. a neutron EDM of 10**-27 e-cm would be sufficient to explain the matter-antimatter asymmetry. Such a n-EDM is about an order-of-magnitude below the best present experimental limits. Our experiment will attempt to search for a n-EDM at the level of 10**-28 e-cm. The figure below shows the evolution of the searches for a n-EDM vs time and the corresponding predictions from various theoretical estimates. The present proposal can be found at Proposal.