Angular scaling in jets

  • Martin Jankowiak
  • Andrew J. Larkoski
Open Access


We introduce a jet shape observable defined for an ensemble of jets in terms of two-particle angular correlations and a resolution parameter R. This quantity is infrared and collinear safe and can be interpreted as a scaling exponent for the angular distribution of mass inside the jet. For small R it is close to the value 2 as a consequence of the approximately scale invariant QCD dynamics. For large R it is sensitive to non-perturbative effects. We describe the use of this correlation function for tests of QCD, for studying underlying event and pile-up effects, and for tuning Monte Carlo event generators.


Jets Hadronic Colliders 


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Copyright information

© SISSA 2012

Authors and Affiliations

  1. 1.SLACMenlo ParkUSA
  2. 2.SITP, Stanford UniversityStanfordUSA

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