Studying of Bs --> K(*)-pi+, K(*)-rho+ decays within supersymmetry

TL;DR

This paper investigates how supersymmetry, specifically gluino-mediated contributions, can explain anomalies in B_s decay measurements and predicts observable effects in branching ratios and CP asymmetries for future experiments.

Contribution

It provides a detailed analysis of supersymmetry effects on B_s decay processes using the mass insertion method, aligning theoretical predictions with experimental data.

Findings

Supersymmetry contributions can reconcile theory with measurements within 2σ.

LR and RL mass insertions significantly affect decay observables.

Future experiments can test the constrained supersymmetry parameter space.

Abstract

Recent results from CDF Collaboration favor a large CP asymmetry in $B_s\rightarrow K^-\pi^+$ decay, while the Standard Model prediction is very small. Moreover, the measurement of its branching ratio is lower than the Standard Model prediction based on the QCD factorization. We compute the gluino-mediated supersymmetry contributions to $B_{s}\to K^{(*)-}\pi^{+}$,$K^{(*)-}\rho^{+}$ decays in the frame of the mass insertion method, and find that for $\frac{m^2_{\tilde{g}}}{m^2_{\tilde{q}}}\leq2$, the theoretical predictions including the LR and RL mass insertion contributions are compatible with the measurements of $B_s\to K^-\pi^+$ decay and $B^0-\bar{B}^0$ mixing within $2\sigma$ ranges. Using the constrained LR and RL mass insertion parameter spaces, we explore the supersymmetry mass insertion effects on the branching ratios, the direct CP asymmetries and the polarization fractions in $B_{s}\to K^{*-}\pi^+, K^{-}\rho^+, K^{*-}\rho^+$ decays. We find the constrained LR and RL insertions can provide sizable contributions to the branching ratios of $B_{s}\to K^{*-}\pi^{+}$,$K^{(*)-}\rho^{+}$ as well as the direct CP asymmetry and the longitudinal polarization of $B_{s}\to K^{*-}\rho^{+}$ decay without conflict with all related data within $2\sigma$ ranges. Near future experiments at Fermi Lab and CERN LHC-b can test our predictions and shrink/reveal the mass insertion parameter spaces.