Quark/Gluon Discrimination

  • Simone Marzani
  • Gregory Soyez
  • Michael Spannowsky
Part of the Lecture Notes in Physics book series (LNP, volume 958)


This chapter is dedicated to the specific applications of substructure techniques to discriminate quark-initiated jets from gluon-initiated jets. We begin with a brief discussion on how to tentatively define quark- and gluon-initiated jets. We then concentrate on two broad classes of observables: (i) shape observables like angularities or energy-correlation functions, and (ii) multiplicity-based observables like the iterated soft-drop multiplicity. In each case, we provide a basic analytic understanding of the tools based on the resummation techniques introduced in Chap. 4. We then discuss the key properties of the tools and assess their performance on Monte-Carlo simulations, highlighting the features which are reproduced by the simple analytic calculations.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Simone Marzani
    • 1
  • Gregory Soyez
    • 2
  • Michael Spannowsky
    • 3
  1. 1.Dipartimento di FisicaUniversità di GenovaGenovaItaly
  2. 2.Institut de Physique TheoriqueCNRS UMR 3681, CEA SaclayGif-sur-Yvette cedexFrance
  3. 3.Department of Physics, Institute for Particle Physics PhenomenologyDurham UniversityDurhamUK

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