1,422 research outputs found
Sex as a Variable: A Bibliography of Women in Libraries 1975-1985
published or submitted for publicatio
PHENIX and the Reaction Plane: Recent Results
During the past several years, experiments at RHIC have established that a
dense partonic medium is produced in Au+Au collisions at sqrt(s)=200 GeV.
Subsequently, a primary goal of analysis has been to understand and
characterize the dynamics underlying this new form of matter. Among the many
probes available, the measurements with respect to the reaction plane has
proven to be crucial to our understanding of a wide range of topics, from the
hydrodynamics of the initial expansion of the collision region to high-pt jet
quenching phenomena. Few tools have the ability to shed light on such a wide
variety of observables as the reacion plane. In this article, we discuss recent
PHENIX measurements with respect to the reaction plane, and the implications
for understanding the underlying physics of RHIC collisions.Comment: 9 pages, 13 figures, Submitted for proceedings to the Winter Workshop
on Nuclear Dynamics 2010, Ocho Rios, Jamaic
Event anisotropy of identified , photon and electron compared to charged , , and deuteron in = 200 GeV Au+Au at PHENIX
We report the recent results of event anisotropy analysis focused on in
= 200 GeV Au+Au collisions at PHENIX.Comment: 4 pages, 3 figures, contribution to the proceedings of the 17th
International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions
(Quark Matter, Oakland, January 11-17, 2004). To appear in the proceedings
(Journal of Physics G
Jet Fragmentation in Vacuum and Medium with gamma-hadron Correlations in PHENIX
Jet fragmentation in p+p and Au+Au collisions is studied via back-to-back
correlations of direct photons and charged hadrons. The direct photon
correlations are obtained by statical subtraction of the background from decay
photons. Results on the nuclear modification to the associated charged hadron
yields are reviewed. Further studies of jet fragmentation in p+p using isolated
direct photons are also presented. A kT-smeared LO pQCD calculation is used to
interpret the data. The sensitivity of the data to the underlying fragmentation
function is tested and the results are found to be compatible with expectations
of a sample dominated by quark jet fragmentation.Comment: Talk presented at Hot Quarks 2010, June 21-26, La Londe Les Maures,
France. To be published in Journal of Physics: Conference Series (JPCS
Measurement of Open Heavy Flavor Production with Single Muons in p+p and d+Au Collisions at RHIC
Heavy flavor production in hadronic collisions is dominated by gluonic
processes and so is a sensitive probe of the gluon structure function in the
nucleon and its modification in nuclei. A study of heavy flavor production in
p+p and d+Au collisions in various kinematic regions presents an opportunity to
probe cold nuclear medium effects; parton shadowing, color glass condensate,
initial state energy loss, and coherent multiple scattering in final state
interactions. The PHENIX muon arms cover both forward and backward directions
in the rapidity range of . We investigate single muon
production from open heavy flavor and light mesons decay in p+p and d+Au
collisions at forward and backward rapidity.Comment: Strangeness in Quark Matter, 2006, UCL
v4 for identified particles at RHIC from viscous hydrodynamics
Using ideal and viscous hydrodynamics, the ratio of azimuthal moments
v4/(v2)^2 is calculated for pions, protons, and kaons in sqrt{s}=200 A*GeV
Au+Au collisions. For any value of viscosity here is little dependence on
particle species. Ideal hydrodynamics and data show a flat curve as a function
of pt. Adding viscosity in the standard way destroys this flatness. However, it
can be restored by replacing the standard quadratic ansatz for delta f (the
viscous correction to the distribution function at freeze-out) with a weaker
momentum dependence.Comment: Proceedings of Hot Quarks 2010, 21-26 June 2010 La Londe Les Maures,
4 pages, 2 figure
Heavy-Flavor Measurements by the PHENIX Experiment at RHIC
In recent years, PHENIX has studied many important observables related to
heavy-flavor physics through their leptonic decay measurements including the
invariant yield of electrons from nonphotonic sources, and prompt single muons,
both of which are dominated by D and B mesons. Charm and beauty cross-sections
were measured and compared through single lepton, and lepton-hadron
correlations in p+p collisions at = 200 GeV. Observables for
quarkonia production such as invariant yield and polarization were also
measured in p+p collisions. In Au+Au collisions, preliminary results for the
for single electrons and a 90% CL upper limit for the suppression of
s were produced. And in +Au collisions, a preliminary
study for production in different centrality ranges was extracted.Comment: 8 pages, 9 figures, International Conference on Strangeness in Quark
Matter Conference 2009 Proceeding
Excitation functions of baryon anomaly and freeze-out properties at RHIC-PHENIX
The intermediate region (2 - 5 GeV/) in central Au+Au collisions at
RHIC has a rich physics content. The (anti)proton to pion ratio at the
intermediate gives us a powerful tool to investigate the bulk properties
of the hot and dense matter created at RHIC and their hadronization processes.
We present the preliminary results of identified charged hadron spectra at the
lower beam energies at RHIC. The excitation function of (anti)proton to pion
ratios from SPS to RHIC are shown. We also discuss the onset of the baryon
enhancement at the high energy heavy ion collisions.Comment: 4 pages, 3 figures, Quark Matter 2006 conference proceeding
High p_T identified particles in PHENIX: data vs. theory
Two of the most interesting experimental results of heavy-ion reactions at
RHIC collider energies are in the hard scattering sector where central Au+Au
data show a very different behaviour compared to p+p and peripheral Au+Au
collisions. The so-called ``high p_T pi^0 suppression'' and the ``anomalous''
baryon/meson ratio observed by PHENIX in central Au+Au collisions at
sqrt(s_{NN}) = 200 GeV are reviewed and compared to various theoretical
calculations based on different strongly interacting medium scenarios.Comment: To appear in the proceedings of 19th Winter Workshop on Nuclear
Dynamics, Breckenridge, Colorado, US, March 8-15, 200
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