Measurement of Time-Dependent CP Asymmetry in B0->D^(*)+-pi-+ Decays and Constraints on |sin(2beta+gamma)|

TL;DR

This paper reports a preliminary measurement of CP asymmetry in B0 decays, providing constraints on the CKM unitarity triangle angles, notably setting a lower bound on |sin(2beta+gamma)| and excluding zero at high confidence.

Contribution

It presents the first time-dependent CP asymmetry measurement in B0->D^(*)+-pi-+ decays and constrains the CKM angle combination |sin(2beta+gamma)|.

Findings

|sin(2beta+gamma)| > 0.69 at 68% CL

Excluded sin(2beta+gamma) = 0 at 83% CL

Analyzed 88 million B meson decays

Abstract

We present preliminary results of a time-dependent measurement of CP-violating asymmetry in fully reconstructed B0->D^(*)+-pi-+ decays in a data sample of approximately 88 million Y(4S)->BB decays collected with the BaBar detector at the PEP-II asymmetric-energy B factory at SLAC. We interpret the results in terms of the angles of the Cabibbo-Kobayashi-Maskawa unitarity triangle, and set the bound |sin(2beta+gamma)|>0.69 at 68% confidence level. We exclude sin(2beta+gamma) = 0 at 83% confidence level.