CP Asymmetries in B to f_0 K_S Decays

TL;DR

This paper analyzes the CP asymmetries in B to f_0(980)K_S decays within the Standard Model using QCD factorization, aiming to understand deviations from sin(2 beta) and constraining the possible range of CP asymmetry deviations.

Contribution

It provides a detailed calculation of Delta S_{f_0 K_S} considering the f_0(980) as a qar{q} state and assesses the theoretical parameter space with experimental constraints.

Findings

Range of Delta S_{f_0 K_S} within 1 sigma: [0.018, 0.033]

Range of Delta S_{f_0 K_S} within 3 sigma: [-0.019, 0.064]

Quantifies possible deviations of CP asymmetry from Standard Model expectations.

Abstract

We consider the branching ratio and the CP asymmetries in B to f_0(980)K_S decay to the end of determining the deviation of the time-dependent CP asymmetry from sin(2 beta) arising from Standard Model physics. We obtain Delta S_{f_0 K_S} within the context of the QCD factorization framework for the B to f_0(980)K_S decay amplitudes assuming the f_0(980) is a q\bar{q} state and employing a random scan over the theoretical parameter space to assess the possible range in Delta S_{f_0 K_S}. Imposing the value of the experimental branching ratio within 1 sigma and 3 sigma, respectively, of its central value as a constraint, we find the range of Delta S_{f_0 K_S} to be [0.018, 0.033] for a scan in which the parameters are allowed to vary within 1 sigma of their central values and the range [-0.019, 0.064] for a scan in which the parameters vary within 3 sigma of their central values.