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Meson loops and the $g_{D^* D π}$ coupling

F. O. Durães·F. S. Navarra·M. Nielsen·M. R. Robilotta
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Abstract

The $D^*Dπ$ form factor is evaluated at low and moderate $Q^2$ in a hadronic loop model, for off-shell $D$ mesons. The results contain arbitrary constants, which are fixed so as to match previous QCD sum rule calculations valid at higher $Q^2$. The form factor obtained in this way was used to extract the coupling constant, which is in very good agreement with the experimental value.

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F. O. Durães, F. S. Navarra, M. Nielsen, M. R. Robilotta. 2004-03-05. Meson loops and the $g_{D^* D π}$ coupling. https://doi.org/10.1590/s0103-97332006000700021

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