Measurement of Neutral B Decay Branching Fractions to Kspi+pi- Final States

TL;DR

This paper reports precise measurements of B-meson decay branching fractions to Kspi+pi- final states, using data from the BaBar detector, and includes the first measurement of CP asymmetry in B0 decays to K*+pi-.

Contribution

It provides new experimental measurements of branching fractions and CP asymmetry in B-meson decays to Kspi+pi- final states, based on a large data sample from BaBar.

Findings

Branching fraction for B0 -> K0pi+pi- is (43.7 +/- 3.8 +/- 3.4) * 10^-6.

Branching fraction for B0 --> K*+pi- is (12.9 +/- 2.4 +/- 1.4) * 10^-6.

CP asymmetry A(K*pi) measured as 0.23 +/- 0.18^{+0.09}_{-0.06}.

Abstract

Branching fraction measurements using B-meson decays to Kspi+pi- are presented. These measurements were obtained by analyzing a data sample of 88.9 million Y(4S) --> BB decays collected with the BaBar detector at the SLAC PEP-II asymmetric-energy B factory. Using a maximum likelihood fit, the following branching fraction results were obtained: Br(B0 -> K0pi+pi- = (43.7 +/- 3.8 +/- 3.4) * 10^-6, Br(B0 --> K{*+}pi-) = (12.9 +/- 2.4 +/- 1.4) * 10$^-6} and Br(B0 --> D-(--> Kspi-)pi+ = (42.7 +/- 2.1 +/- 2.2) * 10^{-6}. The CP violating char ge asymmetry A(K*pi} for the decay B0 --> $K{*+}pi-$ was measured to be A(K*pi} = 0.23 +/- $0.18^{+0.09}_{-0.06}$. For all these measurements the first error is statistical and the second is systematic.