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arXiv · hep-ph/0101031

Analyticity and power corrections in hard-scattering hadronic functions

A. I. Karanikas·N. G. Stefanis
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Abstract

Demanding the analyticity of hadronic observables (calculated in terms of power series of the running coupling) as a {\it whole}, we show that they are free of the Landau singularity. Employing resummation and dispersion-relation techniques, we compute in a unifying way power corrections to two different hard-scattering functions in perturbative QCD: the electromagnetic pion form factor to leading order and the inclusive cross section of the Drell-Yan process. In the second case, the leading nonperturbative power correction in $bΛ_{\rm QCD}$ gives rise to a Sudakov-like exponential factor in the impact parameter space which provides enhancement rather than suppression.

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A. I. Karanikas, N. G. Stefanis. 2006-03-27. Analyticity and power corrections in hard-scattering hadronic functions. https://doi.org/10.1016/s0370-2693(01)00297-0

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