Non-factorization contributions in $D\rightarrow \pi K, KK$ decay

TL;DR

This paper compares different theoretical approaches to D meson decays into pi K and KK, highlighting the significance of soft-gluon effects and their impact on the accuracy of decay rate predictions.

Contribution

It introduces the first calculation of soft-gluon effects using light cone QCD sum rules in D meson decays and compares their impact across various factorization methods.

Findings

Soft-gluon effects are larger than leading order contributions.

QCD factorization with soft-gluon exchanges improves agreement with experimental data.

Soft-gluon effects are small in color-allowed decay channels.

Abstract

We have analyzed the $D\rightarrow \pi K, KK$ decay with the naive factorization (NF), QCD factorization (QCDF)and QCD factorization including soft-gluon exchanges (QCDF+SGE). In these decay channels, the soft-gluon effects are firstly calculated with light cone QCD sum rules. Comparing the three kind approaches, we can find the calculation results have made much more improved QCD factorization (QCDF) than the naive factorization (NF), and the calculation results have also made improved QCD factorization including soft-gluon exchanges (QCDF+SGE) than the QCD factorization (QCDF) in the color-suppressed decay channels. In addition, we find the soft-gluon effects are larger than the leading order contributions, and the calculation results are close to the experimental data for the color-suppressed decay channels. In color-allowed decay channel $D^{0}\rightarrow \pi^{+} K^{-}$, the soft-gluon effects are small and we should consider other power terms, such as final state interaction and annihilation effects.