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Pileup and underlying event mitigation with iterative constituent subtraction

  • P. BertaEmail author
  • L. Masetti
  • D.W. Miller
  • M. Spousta
Open Access
Regular Article - Experimental Physics
  • 49 Downloads

Abstract

The hard-scatter processes in hadronic collisions are often largely contaminated with soft background coming from pileup in proton-proton collisions, or underlying event in heavy-ion collisions. This paper presents a new background subtraction method for jets and event observables (such as missing transverse energy) which is based on the previously published Constituent Subtraction algorithm. The new subtraction method, called Iterative Constituent Subtraction, applies event-wide implementation of Constituent Subtraction iteratively in order to fully equilibrate the background subtraction across the entire event. Besides documenting the new method, we provide guidelines for setting the free parameters of the subtraction algorithm. Using particle-level simulation, we provide a comparison of Iterative Constituent Subtraction with several existing methods from which we conclude that the new method has a significant potential to improve the background mitigation in both proton-proton and heavy-ion collisions.

Keywords

Jet substructure Hadron-Hadron scattering (experiments) Hard scattering Jets Minimum bias 

Notes

Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited

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Copyright information

© The Author(s) 2019

Authors and Affiliations

  1. 1.PRISMA+ Cluster of Excellence and Institute of PhysicsJohannes Gutenberg University MainzMainzGermany
  2. 2.The Enrico Fermi Institute and the Department of PhysicsUniversity of ChicagoChicagoU.S.A.
  3. 3.Institute of Particle and Nuclear Physics, Faculty of Mathematics and PhysicsCharles UniversityPrague 8Czech Republic

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