Higher-twist corrections to $D\to \pi ,K$ form factors from light-cone sum rules

Abstract

We calculate the $D\to P$ transition form factors within the framework of the light-cone QCD sum rules (LCSR) with the $D$-meson light-cone distribution amplitudes (LCDAs). The next-to-leading power (NLP) corrections to the vacuum-to-$D$-meson correlation function are considered, and the NLP corrections from the high-twist $D$-meson LCDAs and the SU(3) breaking effect from strange quark mass are investigated. Adopting the exponential model of the $D$-meson LCDAs,the predicted SU(3) flavor symmetry breaking effects are $R_{SU(3)}^{+,0}=1.12$ and $R_{SU(3)}^T=1.39$, respectively, which confirms the results from LCSR with pion LCDA. The numerical predictions of the form factors show that the contribution from two-particle higher-twist contributions is of great importance and the uncertainties are dominated by the inverse moment of ${\varphi }_D^{+}(\omega ,\mu )$. With the obtained form factors, the predicted Cabibbo-Kobayashi-Maskawa (CKM) matrix elements are $|V_{cd}|=0.151{}_{-0.043}^{+0.091}{|}_{th.}{}_{-0.02}^{+0.017}{|}_{exp.}$ and $|V_{cs}|=0.89{}_{-0.234}^{+0.467}{|}_{th.}{}_{-0.008}^{+0.008}{|}_{exp.}$.

Comments: To be published in Chinese Physics C