906 research outputs found
Two and Three Particle Flavor Dependent Correlations
The PHENIX collaboration has developed novel methodologies for reliable
extraction of jet functions from two and three particle azimuthal correlation
functions measured at mid-rapidity in Au+Au collisions at GeV.
The extracted jet shape and the yield of jet-associated partner hadrons (per
trigger hadron) are found to vary with particle type and collision centrality,
indicating a significant effect of the nuclear collision medium on the (di)jet
fragmentation process.Comment: Proceedings for Quark Matter 2005 parallel tal
Extraction of jet topology using three particle correlations
Recent theoretical studies have indicated that the topological features of
away-side jet fragments can be significantly altered by medium-induced
modifications. The leading candidates resulting from such modifications are
Mach Cones and deflected jets. We show that three particle correlations are
able to distinguish between these different modification scenarios. Initial
results from an application of the method to Au+Au collisions at RHIC
( GeV) are presented.Comment: 4 pages, 3 figs. Proceedings 2nd International Conference on Hard and
Electromagnetic Probes of High-Energy Nuclear Collisions, June 9-16, 2006,
Asilomar, Pacific Grove, Californi
Identification of exotic jet topologies via three particle correlations in PHENIX
Modifications of jet properties resulting from the coupling of jets to the
strongly interacting matter produced in RHIC collisions are of great current
interest. In recent work, the PHENIX collaboration has applied a novel
technique to the analysis of two particle azimuthal correlations which
extinguishes the harmonic part of the underlying event revealing the true jet
shape. Recent extensions of the method to three particle correlations allow for
a more revealing study of jet topologies in Au+Au collisions at
(=200 GeV).Comment: Poster presented at Quark Matter 200
Centrality Dependence of Two-Particle Correlations in Heavy Ion Collisions
Data from the PHOBOS detector have been used to study two-particle
correlations over a broad range of pseudorapidity. A simple cluster model
parameterization has been applied to inclusive two-particle correlations over a
range of centrality for both Cu+Cu and Au+Au collisions at sqrt(s_NN)=200GeV.
Analysis of the data for Au+Au has recently been extended to more peripheral
collisions showing that the previously-observed rise in cluster size with
decreasing system size eventually reaches a maximum value. Model studies have
been used to quantify the significant effect of limited detector acceptance on
the extracted cluster parameters. In the case of Au+Au, correlations between a
trigger particle with pT>2.5GeV and inclusive associated particles have also
been studied. These reveal the presence of a `ridge' at small relative
azimuthal angle which extends with roughly constant amplitude out to the
largest relative pseudorapidity studied. The large phase-space coverage of the
PHOBOS detector has enabled a quantitative understanding of the so-called
`ZYAM' parameter used in the subtraction of the contribution of elliptic flow
to these triggered correlations.Comment: 4 pages, 4 figures - To appear in the conference proceedings for
Quark Matter 2009, March 30 - April 4, Knoxville, Tennessee (version 2: No
changes from version 1 other than removing line numbers, version 3: Added
full author list and reformatted slightly to keep same number of pages
A New Correlator to Detect and Characterize the Chiral Magnetic Effect
A charge-sensitive in-event correlator is proposed and tested for its
efficacy to detect and characterize charge separation associated with the
Chiral Magnetic Effect (CME) in heavy ion collisions. Tests, performed with the
aid of two reaction models, indicate discernible responses for background- and
CME-driven charge separation, relative to the second- () and
third-order () event planes, which could serve to identify the CME.
The tests also indicate a degree of sensitivity which would enable robust
characterization of the CME via Anomalous Viscous Fluid Dynamics (AVFD) model
comparisons.Comment: 5 pages, 5 Figs.; Published versio
Modification of jet-like correlations in Pb-Au at the SPS
A high statistics study of high- two-particle azimuthal correlations in
Pb-Au at GeV, performed by the CERES experiment at the
CERN-SPS, is presented. A broad away-side correlation with significant dip at
is observed. The shape and magnitude of the correlation
is similar to measurements at RHIC. In comparison to PYTHIA calculations, we
observe a significant excess of soft particles at the away-side. A study of
charge correlations between trigger and associated particles disfavors vacuum
fragmentation of the away-side jet and suggests significant energy transfer of
the hard-scattered parton to the medium.Comment: Proceedings to Quark Matter 2009 Conference, Knoxville, Tennessee,
US
- …