Searches for New Physics in CP Violation from BaBar

TL;DR

This paper reports on searches for new physics via CP violation in charm decays using BABAR data, finding no evidence of CP violation but confirming charm mixing with significant statistical confidence.

Contribution

First comprehensive search for CP violation in charm decays at BABAR, including mixing measurements and various decay channels, with results consistent with the Standard Model.

Findings

Measured charm mixing parameter y_CP = 0.72% with 3.3σ significance

No evidence of CP violation in studied charm decay channels

Results support the existence of charm mixing but do not indicate new physics

Abstract

Results of recent searches for new physics in CP violation in charm decays from the BABAR experiment are presented. These results include a measurement of $D^0$ - $\bar{D}^0$ mixing and searches for CP violation in two-body $D^0$ decays, a search for CP violation in the charm decays $D^{\pm} \to K^0_S K^{\pm}$ and $D^{\pm}_s \to K^0_S K^{\pm}$, $K^0_S \pi^{\pm}$, and a search for direct CP violation in the singly-Cabibbo suppressed $D^{\pm} \to K^+ K^- \pi^{\pm}$ decays. These studies are based on the final dataset collected by BABAR at the PEP-II B factory at SLAC in the period 1999-2008. No evidence of CP violation is found in these charm decays. The measured mixing parameter $y_{CP} = [0.72 \pm 0.18 (stat) \pm 0.12 (syst)]$% excludes the no-mixing null hypothesis with a significance of 3.3$\sigma$.