Search for Bs,d->mumu at LHCb with 300 pb-1

TL;DR

This paper reports a search for rare Bs and Bd meson decays into muon pairs using early LHCb data, setting upper limits on their branching fractions and combining results from multiple datasets.

Contribution

First search for Bs and Bd to mu mu decays at LHCb with 300 pb^{-1} data, establishing new upper limits on their branching fractions.

Findings

BR(Bs->mumu) < 1.6 x 10^{-8} at 95% CL

BR(Bd->mumu) < 5.1 x 10^{-9} at 95% CL

Combined dataset yields BR(Bs->mumu) < 1.5 x 10^{-8} at 95% CL

Abstract

A search for the Bs->mumu and Bd->mumu decays is performed in ~300 pb-1 of pp collisions at sqrt(s) = 7 TeV collected by the LHCb experiment at the Large Hadron Collider at CERN. The measured limit on the branching fraction of the Bs->mumu decay is BR(Bsmumu) < 1.6 10^{-8} at 95% confidence level, while that of the Bd->mumu decay is BR(Bd->mumu) < 5.1 x 10^{-9} at 95% confidence level. A combination with the 2010 dataset of LHCb yields a limit of BR(Bs->mumu) <1.5 x 10^{-8} at 95% confidence level.