Jet Substructure Without Trees
  We present an alternative approach to identifying and characterizing jet substructure. An angular correlation function is introduced that can be used to extract angular and mass scales within a jet without reference to a clustering algorithm. This procedure gives rise to a number of useful jet observables. As an application, we construct a top quark tagging algorithm that is competitive with existing methods. 
Martin Jankowiak and Andrew J. Larkoski
hep-ph hep-ex