Search for CP Violation in B0B0bar Mixing using Partial Reconstruction of B0-->D*-Xl+ nu and a Kaon Tag

TL;DR

This paper reports a search for CP violation in B0 meson mixing using partial reconstruction and kaon tagging, finding no significant asymmetry within experimental uncertainties.

Contribution

It introduces a novel analysis method combining partial reconstruction and kaon tagging to measure CP violation in B0B0bar mixing.

Findings

Measured CP asymmetry consistent with zero

Set new limits on CP violation parameters

Demonstrated effectiveness of partial reconstruction technique

Abstract

We present results of a search for CP violation in B0B0bar mixing with the BABAR detector. We select a sample of B0-->D*-Xl+ nu decays with a partial reconstruction method and use kaon tagging to assess the flavor of the other B meson in the event. We determine the CP violating asymmetry ACP = (N(B0B0) - N(B0bar B0bar))/(N(B0B0) + N(B0bar B0bar))=(0.06+-0.17+0.38-0.32)%, corresponding to delta_CP =1 - |q/p| =(0.29+-0.84+1.88 -1.61)*10^-3.