Measurement of Time-dependent CP-Violating Asymmetries in B^0 -> K^0_S K^0_S K^0_S Decays

TL;DR

This paper reports preliminary measurements of CP asymmetry parameters in B^0 decays to three K^0_S mesons, using data from the BABAR detector, providing insights into CP violation in these decays.

Contribution

First measurement of CP asymmetries in B^0 -> K^0_S K^0_S K^0_S decays with partial reconstruction, combining new and previous results for improved accuracy.

Findings

Measured S = -0.25^{+0.68}_{-0.61} (stat) +/- 0.05 (syst)

Measured C = 0.56^{+0.34}_{-0.43} (stat) +/- 0.04 (syst)

Combined S = -0.63^{+0.32}_{-0.28} (stat) +/- 0.04 (syst)

Abstract

We present preliminary measurements of the CP asymmetry parameters in B^0 -> K^0_S K^0_S K^0_S decays, reconstructing two of the K^0_S into pi^+pi^- and one into pi^0pi^0. In a sample of 227M $B\bar B$ pairs collected by the BABAR detector at the PEP-II B-Factory at SLAC, we find the CP parameters to be S = -0.25^{+0.68}_{-0.61} (stat) +/- 0.05 (syst) and C = 0.56^{+0.34}_{-0.43} (stat) +/- 0.04 (syst). Combining this result with the previous BABAR measurement, obtained from events with three K^0_S decaying into pi^+pi^-, we get S = -0.63^{+0.32}_{-0.28} (stat) +/- 0.04(syst) C = -0.10 +/- 0.25 (stat) +/- 0.05 (syst)