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تسجيل مستخدم جديدCoupling constants calculation of charmed meson with kaon from QCD sum rules
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M.R. Seyedhabashy
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In this research, the strong coupling constants of the $D^*D_s^*K$, $D_1D_{s1}K$, $D^*D_sK$ and $D_1D_{s0}^*K$ 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 $D^*D_s^*K$ and $D^*D_sK$. Our obtained value for $g$ parameter is $0.24pm 0.09$, which is in good agreement with the lower limits of the other existing predictions.
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