Search for the Rare Decay B0_s -> phi mu^+ mu- with the D0 Detector

TL;DR

This paper reports a search for the rare decay B0_s -> phi mu+ mu- using Fermilab Tevatron data, setting the most stringent upper limit on its branching ratio to date.

Contribution

First search for B0_s -> phi mu+ mu- decay at the Tevatron, establishing the tightest upper limit on its branching ratio with 0.45 fb^-1 of data.

Findings

Upper limit on B(B0_s -> phi mu+ mu-) < 4.1 x 10^-6 at 95% C.L.

Normalized upper limit B(B0_s -> phi mu+ mu-)/B(B0_s -> J/psi phi) < 4.4 x 10^-3.

Most stringent upper bound on this decay to date.

Abstract

We present a search for the flavor-changing neutral current decay B0_s -> phi mu+ mu- using about 0.45 fb^-1 of data collected in p \bar p collisions at sqrt{s} =1.96 TeV with the D{\O}detector at the Fermilab Tevatron Collider. We find an upper limit on the branching ratio of this decay normalized to B0_s -> J/psi phi of B(B0_s -> phi mu+ mu-)/B(B0_s -> J/psi phi) < 4.4\times 10^{-3} at the 95% C.L. Using the central value of the world average branching fraction of B0_s -> J/psi phi, the limit corresponds to B(B0_s -> phi mu+ mu-) < 4.1 \times 10^{-6} at the 95% C.L., the most stringent upper bound to date.