Observation and Polarization Measurements of B+- ->phi K_1+- and B+- ->phi K_2*+-

TL;DR

This paper reports the observation and polarization measurements of specific B meson decays involving phi and K resonances using BaBar data, providing new branching fractions and polarization insights.

Contribution

First measurement of branching fractions and polarization for B+- ->phi K_1(1270)+- and B+- ->phi K_2*(1430)+- decays with detailed CP violation parameters.

Findings

Measured branching fractions: (6.1±1.6±1.1)×10^{-6} and (8.4±1.9±0.9)×10^{-6}

Polarization fractions: 0.46 and 0.80 for the two decays

Upper limits set on other related decay modes

Abstract

With the full $\babar$ data sample of 465 million BaBar pairs, we observe the decays B+- ->phi(1020) K_1(1270)+- and B+- ->phi(1020) K_2*(1430) +-. We measure the branching fractions (6.1+-1.6+-1.1)\times 10^{-6} and (8.4+- 1.9+- 0.9)\times 10^{-6} and the fractions of longitudinal polarization 0.46(+0.12-0.13)(+0.03-0.07) and 0.80(+0.09-0.10)+-0.03, respectively. We also report on the B+- ->phi K_0*(1430)+- decay branching fraction of (7.0+-1.3+-0.9)\times10^{-6} and several parameters sensitive to CP violation and interference in the above three decays. Upper limits are placed on the B+- decay rates to final states with phi and K_1(1400)+-, K*(1410)+-, K_2(1770)+-,or K_2(1820)+-. Understanding the observed polarization pattern requires amplitude contributions from an uncertain source.