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arXiv · hep-ph/9803467

$g_{NDΛ_{c}}$ from QCD Sum Rules

F. S. Navarra·M. Nielsen
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Abstract

The $NDΛ_c$ coupling constant is evaluated in a full QCD sum rule calculation. We study the Borel sum rule for the three point function of one pseudoscalar one nucleon and one $Λ_c$ current up to order seven in the operator product expansion. The Borel transform is performed with respect to the nucleon and $Λ_c$ momenta, which are taken to be equal, whereas the momentum $q^2$ of the pseudoscalar vertex is taken to be zero. This coupling constant is relevant in the meson cloud description of the nucleon which has been recently used to explain exotic events observed by the H1 and ZEUS Collaborations at HERA.

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F. S. Navarra, M. Nielsen. 1998-03-26. $g_{NDΛ_{c}}$ from QCD Sum Rules. https://doi.org/10.1016/s0370-2693(98)01247-7

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