Search for the Decay b -> X_s mu+ mu-

TL;DR

This paper reports a search for the rare decay b -> s mu+ mu- in proton-antiproton collisions, setting a new upper limit on its branching fraction that improves upon previous results.

Contribution

The study provides the most stringent upper limit to date on the branching fraction of the decay b -> s mu+ mu- using data from the DO detector at Fermilab.

Findings

Upper limit on B(b -> X_s mu+ mu-) < 3.2 x 10^{-4} at 90% confidence level

The new limit surpasses previous published constraints

Results contribute to understanding flavor-changing neutral currents

Abstract

We have searched for the flavor-changing neutral current decay b -> s mu+ mu- in p pbar collisions at sqrt(s) = 1.8 TeV with the DO detector at Fermilab. We determine the 90% confidence level limit for the branching fraction to be B(b -> X_s mu+ mu-) < 3.2 x 10^{-4}. We argue that this limit is more stringent than the best published limit on this decay rate.