Cabibbo-Suppressed Decays of D^+ \to \pi^+\pi^0, K^+\bar{K}^0, K^+\pi^0

TL;DR

This paper reports improved measurements of certain Cabibbo-suppressed decay modes of the D+ meson using data from CLEO detectors, including new branching fractions and an upper limit on a doubly suppressed decay.

Contribution

It provides the first precise measurements of specific D+ decay branching fractions and sets an upper limit on a doubly Cabibbo-suppressed decay mode.

Findings

Measured BR(D+ -> pi+ pi0) = (1.31 +/- 0.17 +/- 0.09 +/- 0.09) x 10^(-3)

Measured BR(D+ -> K+ K0bar) = (5.24 +/- 0.43 +/- 0.20 +/- 0.34) x 10^(-3)

Set upper limit BR(D+ -> K+ pi0) < 4.2 x 10^(-4) at 90% CL

Abstract

Using a 13.7 fb-1 data sample collected with the CLEO II and II.V detectors, we report new branching fraction measurements for two Cabibbo-suppressed decay modes of the D+ meson: BR(D+ -> pi+ pi0) = (1.31 +/- 0.17 +/- 0.09 +/- 0.09) x 10^(-3)and BR(D+ -> K+ K0bar) = (5.24 +/- 0.43 +/- 0.20 +/- 0.34) x 10^(-3) which are significant improvements over past measurements. The errors reflect statistical and systematical uncertainties as well as the uncertainty in the absolute D+ branching fraction scale. We also set the first 90% confidence level upper limit on the branching fraction of the doubly Cabibbo-suppressed decay mode BR(D+ -> K+ pi0) < 4.2 x 10^(-4).