D vs d: CP Violation in Beta Decay and Electric Dipole Moments
Abstract
The T-odd correlation coefficient D in nuclear beta decay probes CP violation in many theories beyond the Standard Model. We provide an analysis for how large D can be in light of constraints from electric dipole moment (EDM) searches. We argue that the neutron EDM d_n currently provides the strongest constraint on D, which is 10 - 10^3 times stronger than current direct limits on D (depending on the model). In particular, contributions to D in leptoquark models (previously regarded as "EDM safe") are more constrained than previously thought. Bounds on D can be weakened only by fine-tuned cancellations or if theoretical uncertainties are larger than estimated in d_n. We also study implications for D from mercury and deuteron EDMs.
Cite
@article{arxiv.1111.0649,
title = {D vs d: CP Violation in Beta Decay and Electric Dipole Moments},
author = {John Ng and Sean Tulin},
journal= {arXiv preprint arXiv:1111.0649},
year = {2013}
}
Comments
17 pages, 6 figures