On the heavy quark mass expansion for the operator Qbar gamma_5 Q and the charm content of eta, eta'

M. Franz; P. V. Pobylitsa; M. V. Polyakov; K. Goeke

doi:10.1016/s0370-2693(99)00344-5

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arXiv · hep-ph/9810343

On the heavy quark mass expansion for the operator Qbar gamma_5 Q and the charm content of eta, eta'

M. Franz·P. V. Pobylitsa·M. V. Polyakov·K. Goeke

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Abstract

Recently in the context of studies of the intrinsic charm content of the nucleon and of the eta' meson two groups have arrived at different results for the 1/m^3 term of the heavy quark expansion for operator $\bar Qγ_5Q$ differing by the factor of six. We show that the form of both results violates certain general conditions. Using the expression for the axial anomaly with the finite Pauli-Villars regularization we obtain a new expression for 1/m^3 term of the heavy quark expansion for $\bar Qγ_5 Q$. With this new result we obtain an estimate for the constant f_{η'}^{(c)}=-2 MeV.

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M. Franz, P. V. Pobylitsa, M. V. Polyakov, K. Goeke. 1998-10-13. On the heavy quark mass expansion for the operator Qbar gamma_5 Q and the charm content of eta, eta'. https://doi.org/10.1016/s0370-2693(99)00344-5

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