Ed Hinds

Ben Sauer

Mike Tarbutt

The electron electric dipole moment

The Standard Model of elementary particle physics predicts that the electric dipole moment of the electron (the eEDM) is too small to measure. However, modern extensions to the Standard Model predict values in the range accessible to experiment. The eEDM measurement is therefore a search for physics beyond the Standard Model. Since a permanent eEDM violates time-reversal symmetry, it is also deeply connected to the important topic of CP-violation and the apparent asymmetry between matter and antimatter in the universe.

We are now in the middle of making the most sensitive eEDM measurement to date. Our method uses laser, microwave, and radiofrequency manipulation of the quantum states of cold, polar YbF molecules. In order to improve on the previous measurement [1], a new scheme to prepare and detect the molecules has been developed [2], and is project to improve the measurement by an order of magnitude. This project aims to experimentally implement the new scheme and make a new measurement of the eEDM.

[1] J. J. Hudson et. al., Nature 473, 493-496 (2011).

[2] J. A. Devlin, PhD Thesis, Imperial College London.