Coupling constants calculation of charmed meson with kaon from QCD sum rules

Abstract

In this research, the strong coupling constants of the $D^{\ast }{D}_s^{\ast }K$, $D_1{D}_{s1}K$, $D^{\ast }{D}_{s}K$ and $D_1{D}_{s0}^{\ast }K$ vertices are evaluated, using the three-point QCD sum rules. In order to calculate the coupling constant of each vertex, either the kaon or the charmed meson is considered as the off-shell particle. The basic $g$ parameter, in the heavy quark effective theory, is related to the coupling constants of $D^{\ast }{D}_s^{\ast }K$ and $D^{\ast }{D}_{s}K$. Our obtained value for $g$ parameter is $0.24\pm 0.09$, which is in good agreement with the lower limits of the other existing predictions.