Branching Fractions in B -> phi h and Search for Direct CP Violation in B+- -> phi K+-

TL;DR

This paper reports measurements of branching fractions and CP asymmetry in B meson decays involving phi and K mesons, providing insights into penguin-dominated processes and CP violation.

Contribution

First measurements of branching fractions and CP asymmetry in B -> phi K decays using a large data sample from BaBar.

Findings

BF(B+ -> phi K+) = (10.0^{+0.9}_{-0.8} \, stat. \, ext{and} \, 0.5 \, syst.) * 10^{-6}

BF(B0 -> phi K0) = (7.6^{+1.3}_{-1.2} \, stat. \, ext{and} \, 0.5 \, syst.) * 10^{-6}

A_{CP}(B+ -> phi K+) = 0.039 \, ext{with uncertainties}

Abstract

We present preliminary measurements of branching fractions of the b -> s\bar{s}s penguin-dominated decays B+ -> phi K+ and B0 -> phi K0 in a sample of approximately 89 million BBbar pairs collected by the BaBar detector at the PEP-II asymmetric-energy B-meson Factory at SLAC. We determine BF(B+ -> phi K+) = (10.0^{+0.9}_{-0.8} (stat.) \pm 0.5 (syst.)) * 10^{-6} and BF(B^0 -> phi K0) = (7.6^{+1.3}_{-1.2} (stat.) \pm 0.5 (syst.)) * 10^{-6}. Additionally, we measure the charge asymmetry A_{CP}(B+ -> phi K+) = 0.039 \pm 0.086 (stat.) \pm 0.011 (syst.) and set an upper limit on the CKM- and color-suppressed decay B+ -> phi pi+, BF(B+ -> phi pi+) < 0.41 * 10^{-6} (90% CL).