342 research outputs found
Statistical hadronization of charm: from FAIR to the LHC
We discuss the production of charmonium in nuclear collisions within the
framework of the statistical hadronization model. We demonstrate that the model
reproduces very well the availble data at RHIC. We provide predictions for the
LHC energy where, dependently on the charm production cross section, a
dramatically different behaviour of charmonium production as a function of
centrality might be expected. We extend our predictions for charm production
towards the threshold energies, where charm is expected to be measured at the
future FAIR facility.Comment: 4 pages, 3 figures; proceedings of QM200
Quarkonium production in ultra-relativistic nuclear collisions: suppression vs. enhancement
After a brief review of the various scenarios for quarkonium production in
ultra-relativistic nucleus-nucleus collisions we focus on the ingredients and
assumptions underlying the statistical hadronization model. We then confront
model predictions for J/ phase space distributions with the most recent
data from the RHIC accelerator. Analysis of the rapidity dependence of the
J/ nuclear modification factor yields first evidence for the production
of J/ mesons at the phase boundary. We conclude with predictions for
charmonium production at the LHC.Comment: 8 pages, 6 figures, invited paper, Quark Matter 2006 conference,
Shanghai, submitted to J. Phys.
An assessment of J/Psi formation in the light of initial RHIC data
Predictions of J/Psi formation at RHIC via "off-diagonal" combinations of
charm and anticharm quarks in a region of color deconfinement are confronted
with initial data from the PHENIX collaboration. We find that the measured
centrality behavior places significant constraints on the various parameters
which control model calculations of J/Psi formation. Within present statistical
and systematic uncertainties, one can map out a region of parameter space
within which the contribution of formation in a deconfined phase is allowed. As
these uncertainties decrease and new data from d-Au interactions becomes
available, it is expected that definitive tests for the presence of this
formation mechanism will be possible. We anticipate that the rapidity and
transverse momentum spectra will prove decisive for a final determination.Comment: 6 pages, 5 figures, presented at SQM2003, March 12-17, 2003. To be
published in J. Phys.
The Future of Quark Matter at RHIC
Projected annual results for heavy particle and high-p_{T} correlation
studies at future RHICII luminosities.Comment: 8 pages, 3 figures. Proceedings for Quark Matter 2006, Shanghai,
Chin
Jets in Nuclear Collisions: Status and Perspective
I review the status and future directions of jet-related measurements in high
energy nuclear collisions and their application as a probe of QCD matter.Comment: Summary talk, Hard Probes 2004, Ericeira, Portugal, Nov. 4-10, 2004;
8 pages, 5 figures; v2 has minor correction
Jet quenching and direct photon production
Jet quenching effect has been investigated in the direct photon production,
based on a realistic data-constrained (3+1) dimensional hydrodynamic
description of the expanding hot and dense matter, a reasonable treatment of
the propagation of partons and their energy loss in the fluid, and a systematic
study of the main sources of direct photons. Our resultant \pt spectra agree
with recent PHENIX data in a broad \pt range. Parton energy loss in the
plasma eventually effect significantly direct photon production from
fragmentation and jet photon conversion, similar to hadron suppression in
central heavy ion collisions. But this only causes about 40% decrease in the
total production of direct photons, due to the mixture with other direct photon
sources.Comment: 6 pages and 3 figures, To appear in the proceedings of the
International Conference on Strangeness in Quark matter (SQM2008), Beijing,
China, Oct 6-10, 200
Baryonic Effect on chi_cJ Suppression in Au+Au Collisions at RHIC Energies
We predict that initially produced chi_cJ mesons at low transverse momentum
in the central rapidity region are almost dissociated by nucleons and
antinucleons in hadronic matter produced in central Au+Au collisions at RHIC
energies sqrt {s_{NN}}= 130 and 200 GeV. In calculations the nucleon and
antinucleon distributions in hadronic matter are results of evolution from
their freeze-out distributions which well fit the experimental p_T spectra of
proton and antiproton. Any measured chi_cJ mesons at low p_T are generated from
deconfined matter and give an explicit proof of regeneration mechanism
(recombination mechanism).Comment: 10 pages, 3 figures, Latex, a discussion added to the referenc
Exploring the polarization of gluons in the nucleon
We give an overview of the current status of investigations of the
polarization of gluons in the nucleon. We describe some of the physics of the
spin-dependent gluon parton distribution and its phenomenology in high-energy
polarized hadronic scattering. We also review the recent experimental results.Comment: 10 pages, 13 figures. Talk presented at the "Second Meeting of the
APS Topical Group on Hadronic Physics", Nashville, Tennessee, October 22-24,
2006. Reference adde
Future Experiments in Relativistic Heavy Ion Collisions
The measurements at RHIC have revealed a new state of matter, which needs to
be further characterized in order to better understand its implications for the
early evolution of the universe and QCD. I will show that, in the near future,
complementary key measurements can be performed at RHIC, LHC, and FAIR. I will
focus on results than can be obtained using identified particles, a probe which
has been the basis for this conference over the past three decades. The
sophisticated detectors, built and planned, for all three accelerator
facilities enable us to measure leptons, photons, muons as well as hadrons and
resonances of all flavors almost equally well, which makes these experiments
unprecedented precision tools for the comprehensive understanding of the
physics of the early universe.Comment: 10 pages, 4 figures, Proceedings for Summary Talk at SQM 2007,
Levoca, Slovakia, June 24-29, 200
Elliptic and triangular flow of identified particles at ALICE
We report on the first measurements of elliptic and triangular flow for
charged pions, kaons and anti-protons in lead-lead collisions at 2.76 TeV
measured with the ALICE detector at the LHC. We compare the observed mass
splitting of differential elliptic flow at LHC energies to RHIC measurements at
lower energies and theory predictions. We test the quark coalescence picture
with the quark number scaling of elliptic and triangular flow.Comment: 4 pages, 5 figures, Quark Matter 2011 conference proceeding
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