Hadronic B Decays to Charmless Final States and to J/psi K*

TL;DR

This paper reports preliminary measurements of charmless B decay branching fractions and B -> J/psi K* decay amplitudes from the BABAR experiment, providing insights into CP violation and decay dynamics.

Contribution

It presents the first measurements of specific charmless B decay modes and detailed decay amplitude analysis for B -> J/psi K*, highlighting new experimental results.

Findings

Measured CP-averaged branching fractions for B -> pi+pi- and B -> K+pi-

Set an upper limit for B -> K+K- decay branching fraction

Found a dominant longitudinal component in B -> J/psi K* decay amplitudes

Abstract

Preliminary results from the BABAR experiment on charmless B decays to charged pions or kaons, and the measurement of the B -> J/psi K* decay amplitudes are presented. The data sample, collected at the asymmetric-energy B-factory PEP-II at SLAC, comprises a total number of 22.7 million Y(4S) decays, corresponding to an integrated on-resonance luminosity of approximately 21 fb-1. We measure the following CP-averaged branching fractions: BR(B -> pi+pi-) = (4.1 +- 1.0(stat) +- 0.7(sys))xE-6 BR(B -> K+pi-) = (16.7 +- 1.6(stat) +1.2-1.7(sys))xE-6 and an upper limit of BR(B -> K+K-) < 2.5xE-6, at 90% confidence limit. The measurement of the J/psi K* decay amplitudes results in R_\perp = 0.160 +- 0.032(stat) +- 0.036(sys), and reveals a dominant longitudinal component. The phase of the longitudinal amplitude shows evidence for non-vanishing final state interaction.