Pileup mitigation at CMS in 13 TeV data
Journal
Journal of Instrumentation
Journal Volume
15
Journal Issue
9
Date Issued
2020
Author(s)
Abstract
With increasing instantaneous luminosity at the LHC come additional reconstruction challenges. At high luminosity, many collisions occur simultaneously within one proton-proton bunch crossing. The isolation of an interesting collision from the additional "pileup"collisions is needed for effective physics performance. In the CMS Collaboration, several techniques capable of mitigating the impact of these pileup collisions have been developed. Such methods include charged-hadron subtraction, pileup jet identification, isospin-based neutral particle "δβ"correction, and, most recently, pileup per particle identification. This paper surveys the performance of these techniques for jet and missing transverse momentum reconstruction, as well as muon isolation. The analysis makes use of data corresponding to 35.9 fb-1 collected with the CMS experiment in 2016 at a center-of-mass energy of 13 TeV. The performance of each algorithm is discussed for up to 70 simultaneous collisions per bunch crossing. Significant improvements are found in the identification of pileup jets, the jet energy, mass, and angular resolution, missing transverse momentum resolution, and muon isolation when using pileup per particle identification. ? 2020 CERN for the benefit of the CMS collaboration..
Subjects
Astrophysics; Luminance; Angular resolution; Bunch crossings; Charged hadrons; Neutral particles; Paper surveys; Particle identifications; Simultaneous collisions; Transverse momenta; Charged particles
Type
journal article