Search for the rare decay B_s^0->mu^+mu^-

TL;DR

This paper reports a search for the rare decay B_s^0->mu^+mu^- using Fermilab data, setting the most stringent upper limit to date, which constrains new physics models beyond the Standard Model.

Contribution

The study provides the most restrictive upper limit on the branching fraction of B_s^0->mu^+mu^- to date, improving previous results by a factor of 2.4.

Findings

No significant excess over background observed.

Upper limit on BR(B_s^0->mu^+mu^-) set at 5.1 x 10^-8.

Results constrain new physics models.

Abstract

We present the results of a search for the flavor changing neutral current decay B_s^0->mu^+mu^- using 6.1 fb^-1 of ppbar collisions at sqrt(s) = 1.96 TeV collected by the D0 experiment at the Fermilab Tevatron Collider. The observed number of B_s^0 candidates is consistent with background expectations. The resulting upper limit on the branching fraction is BR(B_s^0->mu^+mu^-) < 5.1 x 10^-8 at the 95% C.L. This limit is a factor of 2.4 better than that of the previous D0 analysis and the best limit to date.