122547143
Net-proton emission in nucleus-nucleus collisions at high energies
The transverse momentum spectrum and rapidity distribution of net-protons produced in nucleus-nucleus collisions at high energies have been studied by using a two-cylinder model. The calculated results are compared and found to be in agreement with the experimental data of Au-Au collisions at the RHIC and AGS energies, as well as Pb-Pb and S-S collisions at the SPS energies. Linear correlations between the parameters in the model and the logarithmic center-of-mass energy are found.
118607664
Singly and Doubly Charged Projectile Fragments in Nucleus-Emulsion Collisions at Dubna Energy in the Framework of the Multi-Source Model *
The multiplicity distributions of projectile fragments emitted in interactions of different nuclei with emulsion are studied by using a multi-source model. Our calculated results show that the projectile fragments can be described by the model and each source contributes an exponential distribution. As the weighted sum of the folding result of many exponential distributions, a multi-component Erlang distribution is used to describe the experimental data. The relationship between the height (or width) of the distribution and the mass of the incident projectile, as well as the dependence of projectile fragments on target groups, are investigated too.
115903813
Angular Distributions of Target Fragments in Magnesium-Emulsion Collisions at High Energy
122076971
ANGULAR DISTRIBUTIONS OF TARGET BLACK FRAGMENTS IN NUCLEUS NUCLEUS COLLISIONS AT HIGH ENERGY
The experimental results of space, azimuthal, and projected angular distributions of target black fragments produced in silicon-emulsion collisions at 4.5A GeV/c (the Dubna energy) are reported. A multi-source ideal gas model is suggested to describe the experimental angular distributions. The Monte Carlo calculated results are in agreement with the experimental data.
122540755
Particle production in Au–Au collisions at RHIC energies
Abstract An overlapping cylinder model (OCM) is introduced in this Letter which considers three components: the longitudinal flow, transverse flow and the temperature. A comparison of our model calculations in terms of pseudorapidity distributions with the most recent experiments is presented. To describe the experimental data at Relativistic Heavy Ion Collider (RHIC) energies ( s NN =130 and 200 GeV), a relative strong longitudinal flow and two partly overlapping cylinders are needed in the model. The difference between the different centrality events is described by the contribution of leading protons. The other parameter values do not depend on the centrality. The calculated results of the overlapping cylinder model are in agreement with the experimental data at the RHIC energies.
120712528
Alpha emission in krypton–emulsion collisions at 1.7A GeV
Abstract The multiplicity and transverse momentum distributions of alpha projectile fragments emitted in nucleus–nucleus collisions at high energies are investigated. The results calculated by the two-source model are in agreement with the experimental data of krypton–emulsion collisions at 1.7 A  GeV.
124273608
Strange Quark Matter and Strangelets in a Strong Magnetic Field
We study the stability properties of magnetized strange quark matter and strangelets under a strong magnetic field in the MIT bag model. The free energy per baryon of strange quark matter feels a great influence from the magnetic held. At the held strength about 1017 G, the magnetized strange quark matter becomes more stable. Considering the finite size effect, the magnetic influence on strangelets becomes complicated. For a given magnetic held, there exists a critical baryon number, below which the magnetized strangelets have lower energy than the non-magnetized strangelets. For the held strength of 5 × 1017 G, the critical baryon number is Ac ~ 100. Generally, the critical baryon number increases with the decreasing external magnetic held. When the held strength is smaller than 1017 G, the critical baryon number goes up to Ac ~ 105. The stable radius, electric charge, and quark flavor fractions of magnetized strangelets are shown.
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.
122934588
Multi-component Erlang distribution of final-state particles produced in high energy collisions
A unified formula on multiplicity distributions of final-state particles is studied in this paper to describe a variety of experimental data including multiplicity, mass, transverse mass, excitation energy, transverse energy, and transverse momentum distributions. It is assumed that the sources of final-state particles are subjected to the multi-source thermal model and the contributions of sources meet the Erlang distribution. Further the validity of the unified formula in descriptions of different distributions is tested. Experimental data of proton-antiproton $$(p\overline{p}),$$ positron–proton (e+p), electron-proton (e−p), and nucleus-nucleus (AA) collisions are analyzed and found that the distributions of mentioned quantities can be described by the multi-component Erlang distribution.
120288217
Comparing two-Boltzmann distribution and Tsallis statistics of particle transverse momentums in collisions at LHC energies
The transverse momentum distributions of final-state particles produced in collisions at energies available at the Large Hadron Collider (LHC) are studied by using the two-Boltzmann distribution and Tsallis statistics. Experimental distributions described by the two-Boltzmann distribution can be described by the Tsallis statistics. The two-temperature emission described by the two-Boltzmann distribution reflects temperature fluctuation of interacting system. The Tsallis statistics can describe the temperature fluctuation and the degree of non-equilibrium. The results calculated by the two-Boltzmann distribution and the Tsallis statistics are in agreement with the experimental data available at the LHC energies. In some cases, the two-Boltzmann distribution degenerates to (single) Boltzmann distribution.
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.