1210.1855 (Stephen D. Ellis et al.)

Jets and Photons    [PDF]

Stephen D. Ellis, Tuhin S. Roy, Jakub Scholtz

This Letter applies the concept of `jets', as constructed from calorimeter cell four-vectors, to jets composed (primarily) of photons (or leptons). Thus jets become a superset of both traditional objects such as QCD-jets, photons, and electrons, and more unconventional objects such as photon-jets and electron-jets, defined as collinear photons and electrons, respectively. Since standard objects such as single photons become a subset of jets in this approach, standard jet substructure techniques are incorporated into the photon finder toolbox. We demonstrate that, for a single photon identification efficiency of 80% or above, the use of jet substructure techniques reduces the number of QCD-jets faking photons by factors of 2.5 to 4. Depending on the topology of the photon-jets, the substructure variables reduce the number of photon-jets faking single photons by factors of 10 to 10^3 at a single photon identification efficiency of 80%.

View original: http://arxiv.org/abs/1210.1855