Measurements of branching fraction ratios and CP asymmetries in B+/- ->D_CP K+/- decays in hadron collisions

TL;DR

This paper reports the first measurements of CP asymmetries and branching fraction ratios in B+/- decays to D_CP K+/- using hadron collision data, contributing to the understanding of the CKM angle gamma.

Contribution

It presents the first hadron collision-based measurements of CP asymmetries and branching ratios in B+/- decays to D_CP K+/-.

Findings

Measured direct CP asymmetry A_CP+ = 0.39 +/- 0.17(stat) +/- 0.04(syst)

Determined the double ratio R_CP+ = 1.30 +/- 0.24(stat) +/- 0.12(syst)

Results will aid in refining the CKM angle gamma.

Abstract

We reconstruct B+/- -> D K+/- decays in a data sample collected by the CDF II detector at the Tevatron collider corresponding to 1 fb-1 of integrated luminosity. We select decay modes where the D meson decays to either K- pi+ (flavor eigenstate) or K- K+, pi- pi+ (CP-even eigenstates), and measure the direct CP asymmetry A_CP+ = 0.39 +/- 0.17(stat) +/- 0.04(syst), and the double ratio of CP-even to flavor eigenstate branching fractions R_CP+ = 1.30 +/- 0.24(stat) +/- 0.12(syst). These measurements will improve the determination of the CKM angle gamma. They are performed here for the first time using data from hadron collisions.