Observation of a Centrality-Dependent Dijet Asymmetry in Lead-Lead Collisions at {radical}(s{sub NN})=2.76 TeV with the ATLAS Detector at the LHC

Journal Article · Fri Dec 17 04:00:00 EST 2010 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.105.252303· OSTI ID:21554481

Aad, G; Ahles, F; Beckingham, M; Bernhard, R; Bitenc, U; Bruneliere, R; Caron, S; Carpentieri, C; Christov, A; Dahlhoff, A; Dietrich, J; Eckert, S; Fehling-Kaschek, M; Flechl, M; Glatzer, J ^[1]; Abbott, B ^[2]; Abdallah, J; Bosman, M; Casado, M P; Cavalli-Sforza, M ^[3]

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1. Albert-Ludwigs-Universitaet, Fakultaet fuer Mathematik und Physik, Hermann-Herder Strasse 3, D-79104 Freiburg i.Br. (Germany)
2. University of Oklahoma, Homer L. Dodge Department of Physics and Astronomy, 440 West Brooks, Room 100, Norman, Oklahoma 73019-0225 (United States)
3. Institut de Fisica d'Altes Energies, IFAE, Edifici Cn, Universitat Autonoma de Barcelona, ES-08193 Bellaterra (Barcelona) (Spain)

By using the ATLAS detector, observations have been made of a centrality-dependent dijet asymmetry in the collisions of lead ions at the Large Hadron Collider. In a sample of lead-lead events with a per-nucleon center of mass energy of 2.76 TeV, selected with a minimum bias trigger, jets are reconstructed in fine-grained, longitudinally segmented electromagnetic and hadronic calorimeters. The transverse energies of dijets in opposite hemispheres are observed to become systematically more unbalanced with increasing event centrality leading to a large number of events which contain highly asymmetric dijets. This is the first observation of an enhancement of events with such large dijet asymmetries, not observed in proton-proton collisions, which may point to an interpretation in terms of strong jet energy loss in a hot, dense medium.

• OSTI ID: 21554481
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 25 Vol. 105; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ACCELERATORS
ASYMMETRY
AUGMENTATION
BARYON-BARYON INTERACTIONS
BARYONS
CALORIMETERS
CENTER-OF-MASS SYSTEM
CERN LHC
CHARGED PARTICLES
COLLISIONS
CYCLIC ACCELERATORS
ELEMENTARY PARTICLES
ENERGY
ENERGY LOSSES
ENERGY RANGE
FERMIONS
HADRON-HADRON INTERACTIONS
HADRONS
INTERACTIONS
IONS
JETS
KINETIC ENERGY
LEAD IONS
LOSSES
MEASURING INSTRUMENTS
NUCLEON-NUCLEON INTERACTIONS
NUCLEONS
PARTICLE INTERACTIONS
PROTON-NUCLEON INTERACTIONS
PROTON-PROTON INTERACTIONS
STORAGE RINGS
SYNCHROTRONS
TEV RANGE
TEV RANGE 01-10
TRANSVERSE ENERGY