A study of the gηcD*D coupling constant from the QCD sum rules

37th Brazilian Meeting on Nuclear Physics

Rodrigues, B. Osório^1,3 ; Bracco, M.E.^2 ; Zanetti, C.M.^2

Instituto de Física, Universidade Do Estado Do Rio de Janeiro, Rua São Francisco Xavier 524, Rio de Janeiro, RJ

20550-900, Brazil^1

Faculdade de Tecnologia, Universidade Do Estado Do Rio de Janeiro, Rod. Presidente Dutra Km 298, Pólo Industrial, Resende, RJ

27537-000, Brazil^2

Centro Brasileiro de Pesquisas Físicas, Rua Xavier Sigaud 150, Rio de Janeiro, RJ

22290-180, Brazil^3

关键词: Coupling constants;    Form factors;    Non-perturbative effects;    QCD sum rules;    Tensor structures;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/630/1/012035/pdf
DOI  :  10.1088/1742-6596/630/1/012035

来源: IOP

【 摘 要 】

In this work, we calculate the form factor and the coupling constant of the charmed vertex ηcD∗D using the QCD sum rules (QCDSR) for the case where the D∗ meson is considered off-shell. This is accomplished by using not only the perturbative contribution of the OPE series but also the non-perturbative effects of the gluon condensates. The form factor of this vertex presents two tensor structures, both of which were analysed. The coupling constant is obtained by the extrapolation of the exponentially parametrized form factor curve to the pole of the D∗ meson.