The Search for Time-Reversal Violation Using Pear-Shaped Nuclei in the FRIB-Era

Jaideep Singh, Michigan State University
Wednesday, Jan 13, 4:10 PM - Virtual Nuclear Science Seminar
Online via Zoom

Abstract:  Experimental tests of fundamental symmetries using nuclei and other particles subject to the strong nuclear force have led to the discovery of parity (P) violation and the discovery of charge-parity (CP) violation. It is believed that additional sources of CP-violation may be needed to explain the apparent scarcity of antimatter in the observable universe. A particularly sensitive and unambiguous signature of both time-reversal- (T) and CP-violation would be the existence of an electric dipole moment (EDM). The current generation of EDM searches in a variety of complimentary systems have unprecedented sensitivity to physics beyond the Standard Model. My talk will focus on diamagnetic systems such as Xe-129 and Hg-199 as well as certain rare diamagnetic atoms such as Ra-225 which have pear-shaped nuclei. This uncommon nuclear structure significantly amplifies the observable effect of T, P, & CP-violation originating within the nuclear medium when compared to isotopes with nearly spherical nuclei such as Hg-199. Certain isotopes of Radium (Ra) and Protactinium (Pa) are expected to have enhanced atomic EDMs and will be produced in abundance at FRIB. I will describe the present status of the ongoing EDM search in Ra-225 as well as the prospects for next generation searches for time-reversal violation in both atomic and molecular systems in the FRIB-era.