55th Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics
Monday–Friday, June 3–7, 2024;
Fort Worth, Texas
Session 2A: GPMFC Workshop: Precision Measurements with Molecules
8:55 AM–5:05 PM,
Monday, June 3, 2024
Room: 202CD
Chair: Tanya Zelevinsky, Columbia University
Abstract: 2A.00003 : Probing parity- and time-reversal violating physics with diatomic molecules*
9:30 AM–10:00 AM
Abstract
Presenter:
David DeMille
(University of Chicago and Argonne National Laboratory)
Author:
David DeMille
(University of Chicago and Argonne National Laboratory)
The small energy spacing between opposite-parity levels in molecules enhances their sensitivity to parity-violating (PV) effects. This talk will discuss experiments that leverage this enhancement for several distinct purposes. In the ZOMBIES experiment, we seek to measure the strength of hyperfine-like PV effects that are depend explicitly on the direction of a nuclear spin. These effects, associated for example with a nuclear anapole moment, arise within the Standard Model (SM) and conserve time-reversal symmetry (T). However, they probe details of the electroweak interaction that are intertwined with the strong interaction, which have evaded both experimental measurements and precise theoretical predictions. In the ACME experiment, we seek to detect an electric dipole moment (EDM) along the spin axis of the electron. This effect violates both P and T symmetries; It can arise at an observable level due only to physics beyond the SM, and its appearance is ubiquitous in theories with new physics above the TeV scale. Prior generations of ACME improved the world-best sensitivity to the electron EDM by a factor of 100, and a new generation, ACME III, is underway with the goal to make another order of magnitude improvement. Finally, we describe experimental efforst to detect a P- and T-violating nuclear Schiff moment (an effect closely related to an EDM). This type of measurement is sensitive to a different and broader range of new sources of underlying physics than the electron EDM. One such experiment, CeNTREX, uses methods similar to those of ACME and aims for improved sensitivty to the proton EDM in particular. Finally, a new effort will use ultracold, trapped molecules containing radioactive nuclei with an octupole deformation that enhances the Schiff moment caused by new physics, In particular, we aim to assemble ultracold 223FrAg (francium-silver) molecules and use them to achieve improved sensitivity to P- and T-violation in the hadronic sector by a factor of 1000 relative to existing limits. With this approach it is plausible to probe energy scales even much higher than those probed by current electron EDM searches.
*This work supported by the US Department of Energy, National Science Foundation, Heising-Simons Foundation, Gordon and Betty Moore Foundation, and Alfred P. Sloan Foundation.