Relating direct CP violation in D decays and the forward-backward asymmetry in $t\bar t$ production

TL;DR

This paper explores a potential link between observed anomalies in top quark production asymmetry and CP violation in charm decays, proposing a minimal scalar doublet model as a common new physics source.

Contribution

It demonstrates that a minimal scalar doublet model can simultaneously explain anomalies in top quark asymmetry and charm CP violation without additional modifications.

Findings

The model accounts for the large forward-backward asymmetry in top quark production.

It predicts a CP violation in charm decays of the observed order of magnitude.

The proposed explanation links two separate anomalies through a common new physics framework.

Abstract

The CDF and LHCb experiments have recently provided two intriguing hints for new physics: a large forward-backward asymmetry in $t\bar t$ production, and a direct CP asymmetry in D decays of order a percent. In both cases, flavor non-universal interactions are required in the up sector, raising the possibility that the two effects come from one and the same new physics source. We show that a minimal model, with an extra scalar doublet, previously suggested to explain the top data, gives -- without any modifications or additions -- a contribution to CP violation in charm decays that is of the right size.