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

Published

Journal Article

Distributions sensitive to the underlying event are studied in events containing one or more charged-particle jets produced in pp collisions at √s=7TeV with the ATLAS detector at the Large Hadron Collider (LHC). These measurements reflect 800μb-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 pTjet in regions transverse to and opposite the leading jet for 4GeV<100GeV. 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 pTjet 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. © 2012 CERN.

Full Text

Duke Authors

Cited Authors

  • Aad, G; Abbott, B; Abdallah, J; Abdel Khalek, S; Abdelalim, AA; Abdinov, O; Abi, B; Abolins, M; Abouzeid, OS; Abramowicz, H; Abreu, H; Acerbi, E; Acharya, BS; Adamczyk, L; Adams, DL; Addy, TN; Adelman, J; Adomeit, S; Adragna, P; Adye, T; Aefsky, S; Aguilar-Saavedra, JA; Aharrouche, M; Ahlen, SP; Ahles, F; Ahmad, A; Ahsan, M; Aielli, G; Akdogan, T; Akesson, TPA; Akimoto, G; Akimov, AV; Akiyama, A; Alam, MS; Alam, MA; Albert, J; Albrand, S; Aleksa, M; Aleksandrov, IN; Alessandria, F; Alexa, C; Alexander, G; Alexandre, G; Alexopoulos, T; Alhroob, M; Aliev, M; Alimonti, G; Alison, J; Allbrooke, BMM; Allport, PP; Allwood-Spiers, SE; Almond, J; Aloisio, A; Alon, R; Alonso, A; Alvarez Gonzalez, B; Alviggi, MG; Amako, K; Amelung, C; Ammosov, VV; Amorim, A; Amram, N; Anastopoulos, C; Ancu, LS; Andari, N; Andeen, T; Anders, CF; Anders, G; Anderson, KJ; Andreazza, A; Andrei, V; Anduaga, XS; Anger, P; Angerami, A; Anghinolfi, F; Anisenkov, A; Anjos, N; Annovi, A; Antonaki, A; Antonelli, M; Antonov, A; Antos, J; Anulli, F; Aoun, S; Aperio Bella, L; Apolle, R; Arabidze, G; Aracena, I; Arai, Y; Arce, ATH; Arfaoui, S; Arguin, JF; Arik, E; Arik, M; Armbruster, AJ; Arnaez, O; Arnal, V; Arnault, C; Artamonov, A; Artoni, G

Published Date

  • October 9, 2012

Published In

Volume / Issue

  • 86 / 7

Electronic International Standard Serial Number (EISSN)

  • 1550-2368

International Standard Serial Number (ISSN)

  • 1550-7998

Digital Object Identifier (DOI)

  • 10.1103/PhysRevD.86.072004

Citation Source

  • Scopus