121985267
PSEUDORAPIDITY DISTRIBUTION SHAPE OF SHOWER PARTICLES IN HIGH ENERGY NUCLEUS-EMULSION COLLISIONS
Abstract The characteristics of the pseudorapidity distribution shape of shower particles produced in high-energy nucleus-emulsion collisions have been studied in this paper. The simple and useful experimental formula, the Gaussian distribution, cannot describe the pseudorapidity distributions with a long tail, two peaks and a plateau. Considering the contributions of the projectile and target protons, the thermalized cylinder picture gives a better description of the experimental data.
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.
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.
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.
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.
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.
121546377
Dependences of charged particle pseudorapidity distributions on impact parameter and center-of-mass energy in nucleus–nucleus collisions at relativistic energies
The centrality and rapidity dependence of charged particles over a wide range of center-of-mass energy are analyzed. In this framework of participant-spectator model, the interacting system of nucleus–nucleus collisions at relativistic energies is divided into four parts (sources): target spectator, target participant, projectile participant and projectile spectator. Each source is treated by using a revised Landau model. The pseudorapidity distributions calculated by four-component Landau model are found to be in agreement with experimental data of the PHOBOS and ALICE collaborations. The distribution height is mainly determined by effective nucleon number and center-of-mass energy; and the distribution width being measured by the revised width in the Landau model and the sources rapidity shifts. Furthermore, we have found two empirical relations for projectile-participant and projectile-spectator (pseudo)rapidity as functions of the center-of-mass energy.
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.
126194289
Pseudorapidity fluctuations of extremely high multiplicity events in high-energy nucleus-nucleus collisions
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.