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arXiv · 0710.1878

ρD^*D^* vertex from QCD sum rules

M. E. Bracco·M. Chiapparini·F. S. Navarra·M. Nielsen
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Abstract

We calculate the form factors and the coupling constant in the $ρD^* D^*$ vertex in the framework of QCD sum rules. We evaluate the three point correlation functions of the vertex considering both $ρ$ and $D^*$ mesons off--shell. The form factors obtained are very different but give the same coupling constant: $g_{ρD^* D^*} = 6.6 \pm 0.31$. This number is 50% larger than what we would expect from SU(4) estimates.

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M. E. Bracco, M. Chiapparini, F. S. Navarra, M. Nielsen. 2007-10-09. ρD^*D^* vertex from QCD sum rules. https://doi.org/10.1016/j.physletb.2007.11.066

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