118540594
Energy and Centrality Dependence of Chemical Freeze-out Thermodynamics parameters
energy and somehow saturates at certain values of Tch in collisions near √ sNN=10 GeV, indicating the limiting temperature in hadronic interactions; meanwhile the baryon chemical potential µB decrease with the collision energy. The saturation temperature is also found to be dependent on partonic interaction. At a given collision energy, it is found that both Tch and µB decrease towards more peripheral collisions in the grand canonical approach. The energy and centrality dependence of other chemical freeze-out parameters, strangeness chemical potential µS , strangeness undersaturation factor S , and the volume of the fireball V are also presented in this paper. The chemical potential ratio µs/µB is also compared with lattice QCD calculation. The AMPT default model gives better descriptions on both the particle yields and the chemical freeze-out parameters than those from the AMPT string-melting model.
120498489
Elliptic flow in a hadron transport model
We present elliptic flow v2 as a function of freeze-out time, transverse momentum for π, K, nucleon, Λ, Ξ and Ω in Au+Au collisions at within two transport approaches (RQMD and UrQMD). The presence of mass ordering and NCQ scaling in the string-hadron model suggests that hadronic interactions do contribute to the observed particle-type dependence of v2 as well.
17224426
New results for hadronic collisions in the framework of the Parton-Based Gribov-Regge Theory
Abstract We recently proposed a new approach to high energy nuclear scattering, which treats hadronic collisions in a sophisticated way. Demanding theoretical consistency as a minimal requirement for a realistic model, we provide a solution for the energy conservation, screening problems and identical elementary interactions, the so-called “Parton-Based Gribov-Regge Theory” including enhanced diagrams. We can now present some of our results for SPS and RHIC energies.
15711757
Thermal Equilibrium and Non-uniform Longitudinal Flow in Relativistic Heavy Ion Collisions
A model with non-uniform flow in the longitudinal direction is proposed for the relativistic heavy-ion collisions and compared with the 14.6 A GeV/c Si-Al and 10.8 A GeV/c Au-Au collision data. The stronger influence of transparency on the distribution of heavier produced particles and the larger stopping in the heavier collision system are accounted for by using a new geometrical parameterization picture. The central dips in the proton and deuteron rapidity distributions for Si-Al collision are reproduced.
131941483
Selfaffine analysis for the dynamical fluctuations inside jets produced in high-energy hadron hadron collisions
1752055
On transverse momentum event–by–event fluctuations in string hadronic models
Abstract. Transverse momentum event–by–event fluctuations are studied within the string–hadronic model of high energy nuclear collisions, LUCIAE. Data on non–statistical $p_T$ fluctuations in p+p interactions are reproduced. Fluctuations of similar magnitude are predicted for nucleus–nucleus collisions, in contradiction to the preliminary NA49 results. The introduction of a string clustering mechanism (Firecracker Model) leads to a further, significant increase of $p_T$ fluctuations for nucleus–nucleus collisions. Secondary hadronic interactions, as implemented in LUCIAE, cause only a small reduction of $p_T$ fluctuations.
118242080
Multiplicity and Transverse Energy Distributions in Au-Au and Pb-Pb Collisions
The multiplicity and transverse energy distributions in high-energy nucleus-nucleus collisions are described by a geometrical model, namely the participant-spectator model. The calculated results are compared and found to be in agreement with the experimental data on Au-Au collisions at the RHIC energy and Pb-Pb collisions at the SPS energy.
118223181
Emission of Shower Particles in High-Energy Neutrino-Emulsion Collisions
122895317
Dependence of charged particle pseudorapidity distributions on centrality and energy in p(d)A collisions at high energies
The pseudorapidity distributions of charged particles produced in deuteron-gold (d-Au) and proton-emulsion (p-Em) collisions at high energies are studied in the framework of the two-cylinder model. The experimental results of nuclear reactions induced by protons and deuterons [p(d)A collisions] can be simply described by this model. The dependencies of parameter values on centrality for d-Au collisions and on nucleon-nucleon center-of-mass energy for p-Em collisions are obtained. The formula obtained by this model is a unified formula in the description of (pseudo)rapidity distributions of final-state particles produced in different interactions over an energy range from intermediate accelerator energy to ultrahigh cosmic-ray energy.
120981543
UNIFIED DESCRIPTION OF (PSEUDO)RAPIDITY DISTRIBUTIONS OF FINAL-STATE PARTICLES PRODUCED IN COLLISIONS AT RELATIVISTIC ENERGIES
The paper presents a fit to rapidity distributions of various hadrons measured in heavy-ion experiments at different beam energies. As examples distributions of various identified hadron species measured at GSI SIS and at BNL RHIC are presented and very good agreement between the fit and the data is found. The basis of the fits is a simple Feynman gas model, namely the two-cylinder gas model, for secondary particle production. The model assumption is that there are projectile and target cylinders that are the sources of emitted particles. The conjecture is that at low and intermediate energies the cylinders overlap totally, at high energy the cylinders overlap partly, while at very high energy a gap appears between the two cylinders.
56154903
Transverse Momentum Distributions of Final-State Particles Produced in Soft Excitation Process in High Energy Collisions
Transverse momentum distributions of final-state particles produced in soft process in proton-proton (pp) and nucleus-nucleus (AA) collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies are studied by using a multisource thermal model. Each source in the model is treated as a relativistic and quantum ideal gas. Because the quantum effect can be neglected in investigation on the transverse momentum distribution in high energy collisions, we consider only the relativistic effect. The concerned distribution is finally described by the Boltzmann or two-component Boltzmann distribution. Our modeling results are in agreement with available experimental data.