Suppression of Away-Side Jet Fragments with Respect to the Reaction Plane in Au+Au Collisions at s_NN) = 200 GeV

Journal Article · Sat Jan 01 00:00:00 EST 2011 · Physical Review C

DOI:https://doi.org/10.1103/PhysRevC.84.024904· OSTI ID:1021972

Adare, A. ^[1]; Awes, Terry C ^[2]; Cianciolo, Vince ^[2]; Efremenko, Yuri ^[3]; Enokizono, Akitomo ^[4]; Read, Jr, Kenneth F ^[2]; Silvermyr, David O ^[2]; Sorensen, Soren P ^[5]; Stankus, Paul W ^[2]

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1. University of Colorado, Boulder
2. ORNL
3. University of Tennessee, Knoxville (UTK) & Oak Ridge National Laboratory (ORNL)
4. Oak Ridge National Laboratory (ORNL)
5. University of Tennessee, Knoxville (UTK)

Pair correlations between large transverse momentum neutral pion triggers (p{sub T}=4-7 GeV/c) and charged hadron partners (p{sub T}=3-7 GeV/c) in central (0%-20%) and midcentral (20%-60%) Au+Au collisions at {radical}{ovr S{sub NN}}=200 GeV are presented as a function of trigger orientation with respect to the reaction plane. The particles are at larger momentum than where jet shape modifications have been observed, and the correlations are sensitive to the energy loss of partons traveling through hot dense matter. An out-of-plane trigger particle produces only 26{+-}20% of the away-side pairs that are observed opposite of an in-plane trigger particle for midcentral (20%-60%) collisions. In contrast, near-side jet fragments are consistent with no suppression or dependence on trigger orientation with respect to the reaction plane. These observations are qualitatively consistent with a picture of little near-side parton energy loss either due to surface bias or fluctuations and increased away-side parton energy loss due to a long path through the medium. The away-side suppression as a function of reaction-plane angle is shown to be sensitive to both the energy loss mechanism and the space-time evolution of heavy-ion collisions.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 1021972
• Journal Information: Physical Review C, Vol. 84, Issue 2; ISSN 0556--2813
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
COLLISIONS
CORRELATIONS
ENERGY LOSSES
FLUCTUATIONS
FUNCTIONS
GOLD 197 REACTIONS
GOLD 197 TARGET
HADRONS
HEAVY ION REACTIONS
INHIBITION
JETS
MODIFICATIONS
ORIENTATION
PARTICLES
PIONS NEUTRAL
SHAPE
SPACE-TIME
SURFACES
TRANSVERSE MOMENTUM