Speaker: Pinghan Chu Title: The Neutron EDM and the Dressed Spin Abstract: The search of the neutron electric dipole moment provides a very sensitive test of physics beyond the Standard Model(SM). The SM prediction for the nEDM is at the 10^−31 e cm level, below current experimental limit by five orders of magnitude. However, many theoretical models beyond the SM can accommodate a larger value of the nEDM by several orders of magnitude. If a new source of T violation presents in nature, it could be relevant to this hadronic system. The SNS nEDM experiment invokes new techniques to search for the neutron EDM. It proposes to produce high density of ultra-cold neutrons in superfluid 4He. Polarized 3He will be used as a spin-analyzer and a comagnetometer. The rate of neutron absorption on 3He which can be detected from the emitted scintillation light, depends sensitively on the relative spin orientation of the two particles. The different frequencies of the signals in different electric field directions will determine the neutron EDM. The “dressed spin technique