1,755 research outputs found
Pion, Kaon, and (Anti-) Proton Production in Au+Au Collisions at \srt = 62.4 GeV
We report on preliminary results of pion, kaon, and (anti-) proton transverse
momentum spectra (-0.5 < y < 0) in Au+Au collisions at
GeV using the STAR detector at RHIC. The particle identification (PID) is
achieved by a combination of the STAR TPC and the new TOF detectors, which
allow a PID coverage in transverse momentum () up to 7 GeV/c for pions, 3
GeV/c for kaons, and 5 GeV/c for (anti-) protons.Comment: 8 pages, 11 figures, Hot Quarks 2004, July 18-24, 2004, Taos Valley,
New Mexico, US
Lambda-proton correlations in relativistic heavy ion collisions
The prospect of using lambda-proton correlations to extract source sizes in
relativistic heavy ion collisions is investigated. It is found that the strong
interaction induces a large peak in the correlation function that provides more
sensitive source size measurements than two-proton correlations under some
circumstances. The prospect of using lambda-proton correlations to measure the
time lag between lambda and proton emissions is also studied.Comment: 4 pages, 3 figure, revtex style. Two short paragraphs are added at
referees' recommendations. Phys. Rev. Lett. in pres
Nonlinear Enhancement of the Multiphonon Coulomb Excitation in Relativistic Heavy Ion Collisions
We propose a soluble model to incorporate the nonlinear effects in the
transition probabilities of the multiphonon Giant Dipole Resonances based on
the SU(1,1) algebra. Analytical expressions for the multi-phonon transition
probabilities are derived. Enhancement of the Double Giant Resonance excitation
probabilities in relativistic ion collisions scales as for
the degree of nonlinearity and is able to reach values
compatible with experimental data. The enhancement factor is found to decrease
with increasing bombarding energy. [KEYWORDS: Relativistic Heavy Ion
Collisions,Double Giant Resonance]Comment: 12 pages, 2 figure
Mutual heavy ion dissociation in peripheral collisions at ultrarelativistic energies
We study mutual dissociation of heavy nuclei in peripheral collisions at
ultrarelativistic energies. Earlier this process was proposed for beam
luminosity monitoring via simultaneous registration of forward and backward
neutrons in zero degree calorimeters at Relativistic Heavy Ion Collider.
Electromagnetic dissociation of heavy ions is considered in the framework of
the Weizsacker-Williams method and simulated by the RELDIS code. Photoneutron
cross sections measured in different experiments and calculated by the GNASH
code are used as input for the calculations of dissociation cross sections. The
difference in results obtained with different inputs provides a realistic
estimation for the systematic uncertainty of the luminosity monitoring method.
Contribution to simultaneous neutron emission due to grazing nuclear
interactions is calculated within the abrasion model. Good description of CERN
SPS experimental data on Au and Pb dissociation gives confidence in predictive
power of the model for AuAu and PbPb collisions at RHIC and LHC.Comment: 46 pages with 7 tables and 13 figures, numerical integration accuracy
improved, next-to-leading-order corrections include
Deuterons and space-momentum correlations in high energy nuclear collisions
Using a microscopic transport model together with a coalescence after-burner, we study the formation of deuterons in Au + Au central collisions at distributions are strongly affected by the nucleon space-momentum correlations, at the moment of freeze-out, which are mostly determined by the number of rescatterings. This feature is useful for studying collision dynamics at ultrarelativistic energies
A statistical interpretation of the correlation between intermediate mass fragment multiplicity and transverse energy
Multifragment emission following Xe+Au collisions at 30, 40, 50 and 60 AMeV
has been studied with multidetector systems covering nearly 4-pi in solid
angle. The correlations of both the intermediate mass fragment and light
charged particle multiplicities with the transverse energy are explored. A
comparison is made with results from a similar system, Xe+Bi at 28 AMeV. The
experimental trends are compared to statistical model predictions.Comment: 7 pages, submitted to Phys. Rev.
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