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arXiv · hep-ph/9911316

Universality of 1/Q corrections revisited

Mrinal Dasgupta·Lorenzo Magnea·Graham Smye
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Abstract

We provide an exact analytical calculation at the two-loop level in the abelian limit of the leading power correction for the C parameter in e+e- annihilation. We compare our results to the numerical value obtained employing the soft approximation, the abelian part of the Milan factor. We demonstrate that a simple proportionality holds between the leading power corrections to the C parameter and to the longitudinal cross section in the soft region, and we verify that this proportionality holds for the full two-loop abelian contribution computed here. We comment on the possibility of extending this technique to other event shape variables and distributions, as well as to the non-abelian contributions.

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Mrinal Dasgupta, Lorenzo Magnea, Graham Smye. 1999-11-18. Universality of 1/Q corrections revisited. https://doi.org/10.1088/1126-6708%2F1999%2F11%2F025

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