Measurements of Branching Fractions and CP-Violating Asymmetries in B0 -> rho+- h-+ Decays

TL;DR

This paper reports measurements of branching fractions and CP asymmetries in B0 decays to rho pi and rho K, providing insights into CP violation and testing the Standard Model with data from the BABAR experiment.

Contribution

First measurement of CP-violating asymmetries and branching fractions in B0 -> rho+- pi-+ and B0 -> rho- K+ decays using a large data sample from BABAR.

Findings

Branching fraction for B0 -> rho+- pi-+ is (22.6 +- 1.8(stat) +- 2.2(syst)) x 10^-6.

CP asymmetry for B0 -> rho+- pi-+ is -0.18 +- 0.08 +- 0.03.

Branching fraction for B0 -> rho- K+ is (7.3 +1.3 -1.2 +- 1.3) x 10^-6.

Abstract

We present measurements of branching fractions and CP-violating asymmetries in B0 -> rho+- pi-+ and B0 -> rho- K+ decays. The results are obtained from a data sample of 88.9 10^6 Upsilon(4S) -> B Bbar decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. From a time-dependent maximum likelihood fit we measure the charge-averaged branching fractions B(B0 -> rho+- pi-+) = (22.6 +- 1.8(stat) +- 2.2(syst)) 10^(-6) and B(B0 -> rho- K+) = (7.3 +1.3 -1.2 +- 1.3) 10^(-6); and the CP-violating charge asymmetries Acp(rho pi) = -0.18 +- 0.08 +- 0.03 and Acp(rho K) = 0.28 +- 0.17 +- 0.08; the direct CP violation parameter C(rho pi) = 0.36 +- 0.18 +- 0.04 and the mixing-induced CP violation parameter S(rho pi) = 0.19 +- 0.24 +- 0.03; and the dilution parameters dC(rho pi) = 0.28 +0.18 -0.19 +- 0.04 and dS(rho pi) = 0.15 +- 0.25 +- 0.03.