Right-handed Currents Searches and Parity Doubling

Abstract

The extraction of right-handed currents, beyond the Standard Model, faces theoretical challenges from long-distance contributions. We show that these effects can be controlled by combining, for example, studies of $B\to V(1^{-})\gamma$ and $B\to A(1^{+})\gamma$ observables. The sum of the long-distance contributions can be extracted without compromise, and the individual pieces follow from a ratio predicted by theory. This leads to significant reduction in the uncertainty of long-distance contributions. The ideas extend to charm decays and the low $q^2$-region of $B\to V\ell \bar{\ell }$, and open the prospect of checking input affecting the angular $B\to K^{\ast }\mu \mu$-anomaly.

Comments: QCD-Moriond 2018 proceedings, 6pp + 1fig