Lab Home | Phone | Search | ||||||||
|
||||||||
The Standard Model (SM) of particle physics fails to explain dark matter and the current matter-antimatter asymmetry of the universe. Extensions to the SM, such as weak-scale Supersymmetry, may explain these phenomena by positing the existence of new particles and interactions that are asymmetric under time-reversal (T). These theories nearly always predict an electron electric dipole moment (EDM), a T-violating asymmetric charge distribution along the electron’s spin. I will discuss the ACME collaboration’s newly completed EDM search using the polar molecule thorium monoxide (ThO). We performed a spin precession measurement on a cold beam of ThO, looking for the E-field correlations typical for an EDM. A large internal electric field and unique molecular structure provided statistical precision and rejection of common systematics. The result is an upper limit consistent with zero, which is an order of magnitude improvement in sensitivity compared to the previous best limits. Our result constrains T-violating physics at the TeV energy scale, comparable to those studied at the LHC. Host: Michael Di Rosa (C-PCS) |