Y. G. Aditya, K. J. Healey, Alexey A. Petrov
Recent evidence of observation of the flavor-changing neutral current decay $B^0_s \rightarrow \mu^+ \mu^-$ by the LHCb collaboration $\mathcal{B}(B^0_s \rightarrow \mu^+ \mu^-) = (3.2^{+1.5}_{-1.2})\times 10^{-9}$ is consistent with the latest standard model prediction $\mathcal{B_{SM}}(B^0_s \rightarrow \mu^+ \mu^-) = (3.23\pm0.23)\times 10^{-9}$. While New Physics can still affect this decay amplitude, its contribution is certainly not the dominant one. We analyze branching ratios of the decays $B^0_s \rightarrow \mu^+ \mu^- X$, with $X = \gamma$ or $\nu\bar\nu$, which can mimic $B^0_s \rightarrow \mu^+ \mu^-$ on portions of the parameter space where $X$ is soft. We perform a model-independent standard model calculation of those processes incorporating heavy quark and chiral symmetries of QCD. We show that the considered contributions contribute to $B^0_s \rightarrow \mu^+ \mu^-$ at a sub-percent level.
View original:
http://arxiv.org/abs/1212.4166
No comments:
Post a Comment