Measurement of CP Asymmetry in B0 to Ks pi0 pi0 Decays

TL;DR

This paper reports a measurement of time-dependent CP asymmetry in B0 decays to Ks pi0 pi0, providing insights into CP violation with data from the BABAR experiment.

Contribution

First measurement of CP asymmetry parameters in B0 to Ks pi0 pi0 decays using a large dataset at BABAR.

Findings

Measured CP-violation parameter S = 0.72 +/- 0.71 +/- 0.08

Measured direct CP-violation parameter C = 0.23 +/- 0.52 +/- 0.13

Results are consistent with Standard Model expectations.

Abstract

We present a measurement of the time-dependent CP asymmetry for the neutral B-meson decay into the CP = +1 final state Ks pi0 pi0, with Ks -> pi+ pi-. We use a sample of approximately 227 million B-meson pairs recorded at the Upsilon(4S) resonance with the BABAR detector at the PEP-II B-Factory at SLAC. From an unbinned maximum likelihood fit we extract the mixing-induced CP-violation parameter S = 0.72 +/- 0.71 +/- 0.08 and the direct CP-violation parameter C = 0.23 +/- 0.52 +/- 0.13, where the first uncertainty is statistical and the second systematic.