Photon Polarization in the b->s gamma processes in the Left-Right Symmetric Model

TL;DR

This paper explores how the Left-Right Symmetric Model can significantly enhance the right-handed photon polarization in b->s gamma decays, contrasting with the Standard Model's left-handed dominance, and discusses detection prospects.

Contribution

It demonstrates the potential for large right-handed photon polarization in LRSM due to W_L-W_R mixing, helicity flips, and CKM enhancements, expanding understanding of new physics effects.

Findings

Right-handed polarization could be substantially increased in LRSM.

Sensitivity of polarization measurements can probe LRSM parameters.

Complementary to direct searches for right-handed gauge bosons at LHC.

Abstract

The circular-polarization of the photon in the radiative B decays is dominantly left-handed in the Standard Model (SM), but the right-handed polarization may be enhanced in some new physics models with right-handed currents, such as the Left-Right Symmetric Model (LRSM). In this article, we investigate how large this wrong polarization could be within the allowed parameter space of the LRSM. We show that in LRSM, the right-handed polarization of the photon in the $b\to s\gamma$ processes could be largely enhanced by the $W_L-W_R$ mixing contributions because of the helicity flip on the internal top quark line of the penguin diagrams and the enhancement by the CKM factor $V_{ts}^R/V_{ts}^L$. We discuss the sensitivity of the proposed methods to determine the $b\to s\gamma$ photon polarization to the LRSM as well as their complementary role compared to the direct search of right-handed charged gauge bosons at LHC.