Underlying event characteristics and their dependence on jet size of charged-particle jet events in <em>pp</em> collisions at √(s)=7  TeV with the ATLAS detector

ATLAS Collaboration

doi:10.1103/PhysRevD.86.072004

Scientific article

English

Underlying event characteristics and their dependence on jet size of charged-particle jet events in pp collisions at √(s)=7 TeV with the ATLAS detector

Contributors

ATLAS Collaboration

Published in

Physical review. D. Particles, fields, gravitation, and cosmology, vol. 86, no. 07, 072004

Publication date

2012

Abstract

Distributions sensitive to the underlying event are studied in events containing one or more charged-particle jets produced in pp collisions at √s=7 TeV with the ATLAS detector at the Large Hadron Collider (LHC). These measurements reflect 800 μb−1 of data taken during 2010. Jets are reconstructed using the anti-kt algorithm with radius parameter R varying between 0.2 and 1.0. Distributions of the charged-particle multiplicity, the scalar sum of the transverse momentum of charged particles, and the average charged-particle pT are measured as functions of pjetT in regions transverse to and opposite the leading jet for 4 GeV<100 GeV. In addition, the R dependence of the mean values of these observables is studied. In the transverse region, both the multiplicity and the scalar sum of the transverse momentum at fixed pjetT vary significantly with R, while the average charged-particle transverse momentum has a minimal dependence on R. Predictions from several Monte Carlo tunes have been compared to the data; the predictions from Pythia 6, based on tunes that have been determined using LHC data, show reasonable agreement with the data, including the dependence on R. Comparisons with other generators indicate that additional tuning of soft-QCD parameters is necessary for these generators. The measurements presented here provide a testing ground for further development of the Monte Carlo models.

UNIGE affiliation entities

Faculté des sciences / Section de physique / Département de physique nucléaire et corpusculaire

Citation (ISO format)

ATLAS Collaboration. Underlying event characteristics and their dependence on jet size of charged-particle jet events in pp collisions at √(s)=7 TeV with the ATLAS detector. In: Physical review. D. Particles, fields, gravitation, and cosmology, 2012, vol. 86, n° 07, p. 072004. doi: 10.1103/PhysRevD.86.072004

Article (Published version)

Identifiers

PID : unige:40646
DOI : 10.1103/PhysRevD.86.072004

Additional URL for this publication

http://journals.aps.org/prd/abstract/10.1103/PhysRevD.86.072004

Journal ISSN

1550-2368

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166downloads

Creation

03/10/2014 11:33:00

First validation

03/10/2014 11:33:00

Update

13/10/2025 22:21:46

Status update

14/03/2023 21:48:58

Last indexation

10/11/2026 17:09:52