Search for Bs --> mu+ mu- at D0

TL;DR

This paper reports a search for the rare decay Bs --> mu+ mu- at the D0 experiment, setting an upper limit on its branching fraction based on collision data, contributing to understanding of rare B meson decays.

Contribution

First search for Bs --> mu+ mu- decay at D0 with 1.3/fb data, establishing an upper limit on its branching fraction.

Findings

Observed 2 candidate events consistent with background

Set an upper limit on the branching fraction of 1.2e-7

Results constrain new physics models affecting rare B decays

Abstract

We report results from a search for the decay Bs --> mu+ mu- using 1.3/fb of pbar p collisions at sqrt(s)= 1.96 TeV collected by the D0 experiment at the Fermilab Tevatron Collider. We find two candidate events, consistent with the expected background of 1.24 +/- 0.99, and set an upper limit on the branching fraction of B(Bs --> mu+ mu-) < 1.2e-7 at the 95% C.L.