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arXiv · 0805.1337

Soft end-point and mass corrections to the eta' g*g* vertex function

S. S. Agaev·M. A. Gomshi Nobary
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Abstract

Power-suppressed corrections arising from end-point integration regions to the space-like vertex function of the massive eta'-meson virtual gluon transition eta' - g*g* are computed. Calculations are performed within the standard hard-scattering approach (HSA) and the running coupling method supplemented by the infrared renormalon calculus. Contributions to the vertex function from the quark and gluon contents of the eta' -meson are taken into account and the Borel resummed expressions for F_{eta' g*g*}(Q2,ω,η), as well as for F_{eta' g g*}}(Q^{2},ω=\pm 1,η) and F_{eta' g*g*}(Q^{2},ω=0,η) are obtained. It is demonstrated that the power-suppressed corrections \sim (Λ^{2}/Q^{2})^{n}, in the explored range of the total gluon virtuality 1 <Q2 < 25 GeV2, considerably enhance the vertex function relative to the results found in the framework of the standard HSA with a fixed coupling. Modifications generated by the eta ' -meson mass effects are discussed.

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S. S. Agaev, M. A. Gomshi Nobary. 2008-05-09. Soft end-point and mass corrections to the eta' g*g* vertex function. https://doi.org/10.1140/epjc%2Fs10052-008-0524-7

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