Semileptonic $D_{(s)}\to A{\ell }^{+}\nu$ and nonleptonic $D\to K_1(1270,1400)\pi$ decays in LCSR

Abstract

In this work, the transition form factors are calculated for the semileptonic $D_{(s)}\to A{\ell }^{+}\nu$ where $A=a_1,b_1,K_1(1270,1400)$, i.e., $D^{+}\to a_1^0(b_1^0,K_1^0){\ell }^{+}\nu$, $D^0\to a_1^{-}(b_1^{-}){\ell }^{+}\nu$, and $D_s^{+}\to K_1^0{\ell }^{+}\nu$ in the frame work of the light-cone QCD sum rules (LCSR) approach up to the twist-3 distribution amplitudes (DAs). Since the masses of these axial vector mesons are comparable to the charm quark mass, we keep out in our calculations all terms including $m_A/m_c$ in expansion of two--parton DAs. Branching ratio values are estimated for the semileptonic $D_{(s)}\to A\ell \nu$ and nonleptonic $D\to K_1(1270,1400)\pi$ decays. A comparison is also made between our results and predictions of other methods and the existing experimental values.

Comments: 17 pages, 4 figures