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arXiv · hep-ph/9807494

On power corrections in the dispersive approach

G. Grunberg
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Abstract

Power corrections in QCD (both conventional and unconventional ones arising from the ultraviolet region) are discussed within the infrared finite coupling-dispersive approach. It is shown how power corrections in Minkowskian quantities can be derived from the corresponding ones in associated Euclidean quantities through analyticity, allowing a parametrization in term of the Euclidean coupling and a renormalon-free perturbative expansion. It is argued that one should in general expect coefficients functions computed in the true non-perturbative vacuum to differ from the standard perturbative ones, even without assuming new physics. A phenomenology of $1/Q^2$ terms arising from eventual new physics of ultraviolet origin is also set-up. Models for non-perturbative contributions to the (universal) QCD coupling are suggested. Issues of renormalization scheme dependence are commented upon.

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G. Grunberg. 1998-12-08. On power corrections in the dispersive approach. https://doi.org/10.1088/1126-6708%2F1998%2F11%2F006

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