First Measurement of the Permanent Electric Dipole Moment of Radium-225*

Electric dipole moments (EDMs) are signatures of time-reversal ($T$), parity ($P$),\& charge-parity ($CP$) violation. $CP$-violation beyond the Standard Model is generally believed to be required to explain the observed prevalence of matter over antimatter in the universe. Radium-225 ($\tau_{1/2} = 14.7$ d, $I = 1/2$) is mostly sensitive to $T$- and $P$-violating interactions originating within the nucleus. The best limits on these types of exotic interactions are derived from the atomic EDM limit for Mercury-199. Because of its unusual nuclear structure (octupole deformation), Ra-225 is expected to have a physics sensitivity that is a few hundred to a few thousand times higher than Hg-199. Laser cooling \& trapping techniques are performed to collect \& transport the cold Ra atoms into the measurement region. An EDM measurement is then performed by searching for a linear electric field dependent shift in the nuclear spin precession frequency of Ra-225. We will report on the first measurement of the atomic EDM of Ra-225 as well as plans for future improvements.