Ultracold Neutron Electric Dipole Moment Experiment

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Our experiment aims to measure the neutron electric dipole moment (nEDM) more precisely than ever before. A new measurement of the nEDM will place even tighter constraints on theories involving new sources of Charge-Parity (CP) violation beyond the standard model. It is believed these are required in order to explain the predominance of matter over antimatter (baryon asymmetry) in the universe today. Quite generically, the experiment will constrain broad classes of new physics scenarios which do not conserve CP. A new measurement also could impact a long-standing mystery in the standard model, involving the appararent lack of CP violation arising from the strong force. A discovery of a non-zero nEDM would be a major discovery, because it would shed light on a broad range of theories. A key tool in this search is a new source of ultracold neutrons (UCN). UCN are slow moving neutrons that can be stored in material, magnetic, and gravitational bottles. Once they've been confined using such methods, their properties can be studied very carefully to search for deviations from expectations based on the standard model of particle physics. Our scientific collaboration is named the TUCAN (TRIUMF Ultracold Advanced Neutron) collaboration. In the past three years, we have completed a new source of UCN in Canada (at TRIUMF, Vancouver, BC) with the help of collaborators from Japan. New funds for upgrades to the UCN source and for the construction of a new neutron EDM experiment have been secured from the Canada Foundation for Innovation and partner contributions including a substantial contribution from Japan. Once the upgrades are complete, the source is projected to provide the highest density of UCN in the world. The source will be used to advance fundamental physics experiments to unprecedented levels of precision. Our activities over the next three years will involve the completion of the UCN source upgrade and the nEDM experiment construction. We will also use the existing UCN source at TRIUMF for experiments aimed at answering critical questions for the overall success of the experiment.