Progress Towards the ACME III Search for the Electron Electric Dipole Moment

Measurements of the electron electric dipole moment (eEDM) serve as a powerful test for theories of physics beyond the standard model involving high energy time-reversal violating interactions. The ACME II measurement in 2018 reported the current best limit of the eEDM of |de| < 1.1 × 10−29 e · cm (Nature, 562 (2018) 355-360), probing energy scales on the order of 10 TeV (J. High Energ. Phys., 2019 (2019) 59). The ACME collaboration is currently developing a new measurement with the goal of improving the experiment sensitivity by at least an order of magnitude. This new measurement will rely on improvements of the statistical sensitivity of the experiment, and suppression of known systematic error sources. These statistical upgrades include improvements to the molecular beam flux, the detection system, and the experiment precession time. In order to suppress known error sources, we are developing an improved magnetic shielding system, and new glass electric field plates for the precession region. We report here a general overview of the upgrades being developed, and the status of the ACME III measurement of the eEDM.