Determination of Strong Coupling Constant from Inclusive Semileptonic Decays of Charmed Mesons

Employing the heavy quark expansion model with the kinetic scheme, we evaluate αS(mc²), the strong coupling constant at the charm quark mass mc with data on inclusive semileptonic decays of charmed mesons. Using the experimental values of semileptonic decay widths of the D⁰ and the D⁺, the value of αₛ(mc²) is determined to be 0.445±0.009±0.114, where the first uncertainty is experimental and the second systematic. This reported αₛ(mc²) is in good agreement with the value of αₛ(mc²) calculated by running αS(mZ²) at the Z⁰ boson mass mZ with the renormalization group evolution equation. In addition, values of αₛ(mc²) obtained individually from each of the D⁰, D⁺, and Dₛ⁺ mesons are found to be consistent being of the same origin.