Observation of the decay $B_s^0\to\bar{D}^0\phi$

TL;DR

This paper reports the first observation of the decay Bs -> D0bar phi using LHCb data, measuring its branching fraction and comparing it to related decays, with a significance of 6.2 sigma.

Contribution

It provides the first measurement of the decay Bs -> D0bar phi and the ratio of branching fractions involving Bs and Bd decays, expanding understanding of B meson decay modes.

Findings

First observation of Bs -> D0bar phi decay with 6.2 sigma significance.

Measured branching fraction ratio of Bs -> D0bar phi to Bs -> D0bar K*0bar as 0.069 +/- 0.013 (stat) +/- 0.007 (syst).

Determined the ratio of branching fractions for Bs -> D0bar K*0bar and Bd -> D0bar K*0 as 7.8 +/- 0.7 (stat) +/- 0.3 (syst) +/- 0.6 (f_s/f_d).

Abstract

First observation of the decay Bs -> D0bar phi is reported using pp collision data, corresponding to an integrated luminosity of 1.0 fb^-1, collected by the LHCb experiment at a centre-of-mass energy of 7 TeV. The significance of the signal is 6.2 standard deviations. The branching fraction is measured relative to that of the decay Bs -> D0bar K*0bar to be 0.069 +/- 0.013 (stat) +/- 0.007 (syst). The first measurement of the ratio of branching fractions for the decays Bs -> D0bar K*0bar and Bd->D0bar K*0 is found to be 7.8 +/- 0.7 (stat) +/- 0.3 (syst) +/- 0.6 (f_s/f_d), where the last uncertainty is due to the ratio of the Bs and Bd fragmentation fractions.