TY  - JOUR
AU  - Mateu, V.
AU  - Stewart, I. W.
AU  - Thaler, J.
PY  - 2013
DA  - 2013//
TI  - Power corrections to event shapes with mass-dependent operators
T2  - Phys. Rev. D
JO  - Physical Review D
SP  - 014025
EP  - 25pp
VL  - 87
IS  - 1
PB  - Amer Physical Soc
AB  - We introduce an operator depending on the "transverse velocity'' r that describes the effect of hadron masses on the leading 1/Q power correction to event-shape observables. Here, Q is the scale of the hard collision. This work builds on earlier studies of mass effects by Salam and Wicke [J. High Energy Phys. 05 (2001) 061] and of operators by Lee and Sterman [Phys. Rev. D 75, 014022 (2007)]. Despite the fact that different event shapes have different hadron mass dependence, we provide a simple method to identify universality classes of event shapes whose power corrections depend on a common nonperturbative parameter. We also develop an operator basis to show that at a fixed value of Q, the power corrections for many classic observables can be determined by two independent nonperturbative matrix elements at the 10% level. We compute the anomalous dimension of the transverse velocity operator, which is multiplicative in r and causes the power correction to exhibit nontrivial dependence on Q. The existence of universality classes and the relevance of anomalous dimensions are reproduced by the hadronization models in Pythia 8 and Herwig++, though the two programs differ in the values of their low-energy matrix elements.
SN  - 1550-7998
UR  - http://arxiv.org/abs/arXiv:1209.3781
UR  - https://doi.org/10.1103/PhysRevD.87.014025
DO  - 10.1103/PhysRevD.87.014025
LA  - English
N1  - WOS:000314229300005
ID  - Mateu_etal2013
ER  -