FRIF Workshop on First Principles Non-Perturbative QCD of Hadron Jets Universality of Nonperturbative Effects in Event Shapes
نویسندگان
چکیده
Nonperturbative effects in event shape distributions can be characterized by shape functions derived in the eikonal approximation or, equivalently, from soft-collinear effective theory. The use of energy flow operators and the boost invariance of the Wilson lines of soft gluons in the shape functions leads to a proof of universality for power corrections to the mean values of event shapes, without invoking the single gluon approximation.
منابع مشابه
FRIF Workshop on First Principles Non-Perturbative QCD of Hadron Jets Nonperturbative Effects in Event Shapes from Soft-Collinear Effective Theory
Soft-collinear effective theory (SCET) is used to demonstrate factorization for event shape distributions in the two-jet region. The leading nonperturbative power corrections to these distributions can be characterized as shape functions defined in terms of Wilson lines of soft gluons. The relation of these results to the well-known predictions for shifts in the distributions induced by the lea...
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تاریخ انتشار 2008