Universal Nonperturbative Effects in Event Shapes from Soft-collinear Effective Theory
نویسندگان
چکیده
Two-jet event shape distributions, traditionally studied in the language of perturbative QCD, can be described naturally in soft-collinear effective theory. In this language, we demonstrate factorization of event shape distributions into perturbatively-calculable hard and jet functions and nonperturbative soft functions, and show how the latter contribute universal shifts to the mean values of various event shape distributions. Violations of universality in shifts of higher moments can give information on correlations of energy flow in soft radiation.
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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