Eur. Phys. J. Plus (2022) 137: 354
https://doi.org/10.1140/epjp/s13360-022-02576-z

Regular Article

A unique discrimination between new physics scenarios in $b\to s{\mu }^{+}{\mu }^{-}$ anomalies

¹ Indian Institute of Technology Jodhpur, 342037, Jodhpur, India
² Indian Institute of Technology Bombay, 400076, Mumbai, India
³ Centre for High Energy Physics, Indian Institute of Science, 560012, Bangalore, India

^b suman@phy.iitb.ac.in

Received: 5 August 2021
Accepted: 7 March 2022
Published online: 17 March 2022

Abstract

A number of observables related to the $b\to s{\ell }^{+}{\ell }^{-}$ transition show deviations from their standard model predictions. A global fit to the current $b\to s{\ell }^{+}{\ell }^{-}$ data suggests several new physics solutions. Considering only one operator at a time and new physics only in the muon sector, it has been shown that the new physics scenarios (I) $C_9^{\mathrm{NP}}<0$, (II) $C_9^{\mathrm{NP}}=-C_{10}^{\mathrm{NP}}$, (III) $C_9^{\mathrm{NP}}=-C_9^{\prime \mathrm{N}P}$ can account for all data. In this work, we develop a procedure to uniquely identify the correct new physics solution. The scenario II predicts a significantly lower value of $\mathcal{B}(B_s\to {\mu }^{+}{\mu }^{-})$ and can be distinguished from the other two scenarios if the experimental uncertainty comes down by a factor of three. On the other hand, a precise measurement of the CP averaged angular observables $S_9$ in high $q^2$ bin of $B\to K^{\ast }{\mu }^{+}{\mu }^{-}$ decay can uniquely discriminate between the other two scenarios. We propose new methods, in terms of azimuthal angle asymmetries, to measure $S_9$ with the necessary precision.