Study of B+- --> D_CP K+- and D^*_CP K+- decays

TL;DR

This paper measures CP asymmetries in specific B meson decays involving D and D* mesons to CP eigenstates using data from the Belle detector, providing insights into CP violation.

Contribution

The study presents new measurements of CP asymmetries in B meson decays to D and D* mesons with CP eigenstates, using a large data sample from the Belle experiment.

Findings

Measured CP asymmetries with statistical and systematic uncertainties.

Found asymmetries consistent with Standard Model expectations.

Provided data for future CP violation studies.

Abstract

We report a study of the modes D_CP K+- and D^*_CP K+- where D^(*) decays to CP eigenstates. The data sample used contains 275 x 10^6 BB events at the Upsilon(4S) resonance collected by the Belle detector at the KEKB energy-asymmetric e^+ e^- collider. The CP asymmetries obtained for D_CP K are: A_1 = 0.06 +- 0.14 (stat) +- 0.05 (sys), A_2 = -0.12 +- 0.14 (stat) +- 0.05 (sys) and for D^*_CP K : A_1^* = -0.20 +- 0.22 (stat) +- 0.04 (sys), A_2^* = 0.13 +- 0.30 (stat) +- 0.08 (sys).