July 31, 2017 to August 4, 2017
Fermi National Accelerator Laboratory
US/Central timezone

Quark versus Gluon Jet Tagging Using Charged-Particle Constituent Multiplicity with the ATLAS Experiment

Aug 2, 2017, 11:57 AM
Racetrack (Fermi National Accelerator Laboratory)


Fermi National Accelerator Laboratory

Presentation QCD QCD


Francesco Rubbo (SLAC National Accelerator Laboratory)


Distinguishing quark-initiated from gluon-initiated jets is useful for many measurements and searches at the LHC. We present a quark-initiated versus gluon-initiated jet tagger from the ATLAS experiment using the number of reconstructed charged particles inside the jet. The measurement of the charged-particle multiplicity inside jets from Run 1 is used to derive uncertainties on the tagger performance for Run 2. With an efficiency of 60% to select quark-initiated jets, the efficiency to select gluon-initiated jets is between 10 and 20% across a wide range in jet $p_T$ up to 1.5 TeV with about an absolute 5% systematic uncertainty on the efficiencies.

Primary authors

Benjamin Nachman (LBNL) Francesco Rubbo (SLAC National Accelerator Laboratory)

Presentation materials