On Branching Ratios of $B_s$ Decays and the Search for New Physics in $B^0_s\to \mu^+\mu^-$

Robert Fleischer

doi:10.1016/j.nuclphysbps.2013.06.022

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arXiv · 1208.2843

On Branching Ratios of $B_s$ Decays and the Search for New Physics in $B^0_s\to \mu^+\mu^-$

Robert Fleischer

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Abstract

The LHCb experiment has recently established a sizable width difference between the mass eigenstates of the $B_s$-meson system. This phenomenon leads to a subtle difference at the 10% level between the experimental branching ratios of $B_s$ decays extracted from time-integrated, untagged data samples and their theoretical counterparts. Measuring the corresponding effective $B_s$-decay lifetimes, both branching ratio concepts can be converted into each other. The rare decay $B^0_s\to \mu^+\mu^-$ and the search for New Physics through this channel is also affected by this effect, which enhances the Standard-Model reference value of the branching ratio by O(10%), while the effective lifetime offers a new observable to search for physics beyond the Standard Model that is complementary to the branching ratio.

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Robert Fleischer. 2012-08-14. On Branching Ratios of $B_s$ Decays and the Search for New Physics in $B^0_s\to \mu^+\mu^-$. https://doi.org/10.1016/j.nuclphysbps.2013.06.022

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