Observation of Bs->K+K- and Measurements of Branching Fractions of Charmless Two-body Decays of B0 and Bs Mesons in p-pbar Collisions at sqrt(s)=1.96 TeV

TL;DR

This paper reports the first observation of the Bs->K+K- decay mode in proton-antiproton collisions and measures branching fractions of charmless two-body B meson decays, providing new experimental insights into B meson decay processes.

Contribution

The study presents the first observation of the Bs->K+K- decay and measures branching fractions of several charmless B meson decays in p-pbar collisions at 1.96 TeV.

Findings

First observation of Bs->K+K- decay with 236 ± 32 events.

Measured ratio (f_s/f_d)*BR(Bs->K+K-)/BR(B0->K+pi-) = 0.46±0.08(stat.)±0.07(syst.).

Set new upper limits for BR(Bs->K-pi+) and BR(Bs->pi+pi-).

Abstract

We search for decays of the type B0(Bs)->h+h'- (where h,h'= K or pi) in 180 pb-1 of p-pbar collisions collected at the Tevatron by the upgraded Collider Detector at Fermilab. We report the first observation of the new mode Bs->K+K- with a yield of 236 +- 32 events, corresponding to (f_s/f_d)*BR(Bs->K+K-)/BR(B0->K+pi-) = 0.46+-0.08(stat.)+-0.07(syst.), where f_s/f_d is the ratio of production fractions of Bs and B0. We find results in agreement with world averages for the B0 modes, and set the following new limits at 90% CL: BR(Bs->K-pi+) < 5.6*10^{-6} and BR(Bs->pi+pi-) < 1.7*10^{-6}.