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arXiv · hep-ph/0104277

Resummation of non-global QCD observables

M. Dasgupta·G. P. Salam
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Abstract

We discuss issues related to the resummation of non-global observables in QCD, those that are sensitive to radiation in only a part of phase space. Examples of such observables are certain single-hemisphere event shapes in e+e- and DIS. Compared to global observables (those sensitive to all emissions, e.g. the e+e- thrust) a new class of single-logarithmic terms arises. These have been neglected in recent calculations in the literature. For a whole set of single hemisphere e+e- and DIS event shapes, we analytically evaluate the first such term, at order alpha_s^2, and give numerical results for the resummation of these terms in the large-Nc limit.

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M. Dasgupta, G. P. Salam. 2001-04-26. Resummation of non-global QCD observables. https://doi.org/10.1016/s0370-2693(01)00725-0

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