Measurements of charged particle distributions, sensitive to the underlying event, have been performed with the ATLAS detector at the LHC. The measurements are based on data collected using a minimum-bias trigger to select proton-proton collisions at center-of-mass energies of 900 GeV and 7 TeV. The “underlying event” is defined as those aspects of a hadronic interaction attributed not to the hard scattering process, but rather to the accompanying interactions of the rest of the proton. Three regions are defined in azimuthal angle with respect to the highest transverse momentum charged particle in the event, such that the region transverse to the dominant momentum-flow is most sensitive to the underlying event. In each of these regions, distributions of the charged particle multiplicity, transverse momentum density, and average are measured. The data show generally higher underlying event activity than that predicted by Monte Carlo models tuned to pre-LHC data.
Title
Measurement of underlying event characteristics using charged particles in $pp$ collisions at $\sqrt{s}=900$ $GeV$ and 7 TeV with the ATLAS detector
Author
Aad, G. : Albert-Ludwigs-Universität
Abbott, B. : University of Oklahoma
Abdallah, J. : Universitat Autònoma de Barcelona
Abdelalim, A. A. : Université de Genève
Abdesselam, A. : Oxford University
Abdinov, O. : Azerbaijan Academy of Sciences
Abi, B. : Oklahoma State University
Abolins, M. : Michigan State University
Abramowicz, H. : Tel Aviv University
Abreu, H. : Université Paris-Sud
Acerbi, E. : INFN Sezione di Milano
Acharya, B. S. : Università di Udine
Ackers, M. : University of Bonn
Adams, D. L. : Brookhaven National Laboratory
Addy, T. N. : Hampton University
Adelman, J. : Yale University
Anderson, K. J. : University of Chicago
Boveia, A. : University of Chicago
Brubaker, E. : University of Chicago
Canelli, F. : University of Chicago
Choudalakis, G. : University of Chicago
Costin, T. : University of Chicago
Feng, E. J. : University of Chicago
Fiascaris, M. : University of Chicago
Gardner, R. W. : University of Chicago
Gupta, A. : University of Chicago
Jen-La Plante, I. : University of Chicago
Kapliy, A. : University of Chicago
Melachrinos, C. : University of Chicago
Merritt, F. S. : University of Chicago
Onyisi, P. U. E. : University of Chicago
Oreglia, M. J. : University of Chicago
Pilcher, J. E. : University of Chicago
Shochet, M. J. : University of Chicago
Tuggle, J. M. : University of Chicago
Content Type
Article
Published in
Physical Review D
Funding Information
ANPCyT
YerPhI
ARC
BMWF
ANAS
SSTC
CNPq
FAPESP
NSERC
NRC
CFI
CERN
CONICYT
CAS
MOST
NSFC
COLCIENCIAS
MSMT CR
MPO CR
VSC CR
DNRF
DNSRC
Lundbeck Foundation
ARTEMIS
IN2P3-CNRS
CEA-DSM/IRFU
GNAS
BMBF
DFG
HGF
MPG
AvH Foundation
GSRT
ISF
MINERVA
GIF
DIP
Benoziyo Center
INFN
MEXT
JSPS
CNRST
FOM
NWO
RCN
MNiSW
GRICES
FCT
MERYS (MECTS)
MES of Russia
ROSATOM
JINR
MSTD
MSSR
ARRS
MVZT
DST/NRF
MICINN
SRC
Wallenberg Foundation
SER
SNSF
Cantons of Bern and Geneva
NSC
TAEK
STFC
Royal Society
Leverhulme Trust
U.S. Department of Energy
National Science Foundation
Publication Date
2011-05-31
Language
English
Notes
Due to the large number of authors, only the first 20 and the University of Chicago authors are included on the above author list. Please download the article for the complete list of authors.
Record Created
2024-06-14