The strong coupling constant $g_{D^{\ast }D\pi }$ and final-state interactions

Abstract

In this article, we study the contribution from the final-state interactions to the strong coupling constant $g_{D^{\ast }D\pi }$. We take an assumption that the momentum transfers in the strong decay $D^{\ast +}\to D^0{\pi }^{+}$ be large to validate the operator product expansion in the light-cone QCD sum rules. At large momentum transfers, the final-state interactions play an important role, and we should take them into account.

Comments: 7 pages, 1 figure