Measurement of the Ratio of Branching Fractions B(D0 -> K+ pi-)/B(D0 -> K- pi+) using the CDF II Detector

TL;DR

This paper reports a precise measurement of the ratio of branching fractions for D0 meson decays to K+ pi- and K- pi+ using data from the CDF II detector, confirming previous results.

Contribution

First measurement of the branching ratio for D0 -> K+ pi- relative to D0 -> K- pi+ using the CDF II detector at Fermilab.

Findings

Measured R_B = (4.05 +/- 0.21 (stat) +/- 0.11 (syst)) x 10^(-3)

Signal of 2005 +/- 104 D0 -> K+ pi- events

Results are consistent with the world average and other experiments

Abstract

We present a measurement of R_B, the ratio of the branching fraction for the rare decay D0 -> K+ pi- to that for the Cabibbo-favored decay D0 -> K- pi+. Charge conjugate decays are implicitly included. A signal of 2005 +/- 104 events for the decay D0 -> K+ pi- is obtained using the CDF II detector at the Fermilab Tevatron collider. The data set corresponds to an integrated luminosity of 0.35 1/fb produced in p-bar/p collisions at sqrt{s}=1.96 TeV. Assuming no mixing, we find R_B = [ 4.05 +/- 0.21 (stat) +/- 0.11 (syst) ] x 10(-3). This measurement is consistent with the world average, and comparable in accuracy with the best measurements from other experiments.