Search for a Signal on QCD Critical Point in Central Nucleus-Nucleus Collisions

We discuss that the QCD critical point could appear in central collisions in percolation cluster. We suggest using the nuclear transparency effect and the one of the light nuclear production to identify the critical point.Comment: To appear in the proceedings of the 20th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (QM2008), Jaipur, India, February 4-10, 200

Search for a signal on intermediate baryon systems formation in hadron-nuclear and nuclear-nuclear interactions at high energies

We have analyzed the behavior of different characteristics of hadron-nuclear and nuclear-nuclear interactions as a function of centrality to get a signal on the formation of intermediate baryon systems. We observed that the data demonstrate the regime change and saturation. The angular distributions of slow particles exhibit some structure in the above mentioned reactions at low energy. We believe that the structure could be connected with the formation and decay of the percolation cluster. With increasing the mass of colliding nuclei, the structure starts to become weak and almost disappears ultimately. This shows that the number of secondary internuclear interactions increases with increasing the mass of the colliding nuclei. The latter could be a reason of the disintegration of any intermediate formations as well as clusters, which decrease their influence on the angular distribution of the emitted particles.Comment: 2 pages and one figur

Some Properties of the Central pi--Meson Carbon Interactions at 40 Gev/C

We discuss some properties of the central pi--meson carbon reactions at 40 GeV/c. While these results were obtained many years ago they have not been explained completely. We attempt to interpret following: results regime change on the behavior of some characteristics of the events as a function of the centrality; anomaly peak on the angular distributions of the slow protons emitted in these reactions; charge asymmetry on the pi--mesons production in the back hemisphere in lcs. Understanding of the results could help to explain the new ones coming from the modern central experiments at high and ultrarelativistic energies.Comment: To appear in the proceedings of the 10th nternational Workshop on Meson Production, Properties and Interaction (MESON 2008), Krakow, Poland, 6 - 10 June 2008. 4 pages and 4 figure

Production of

The production of $\Delta^{{++}}_{}$ and $\Delta^{0}_{}$ resonances on oxygen nuclei in 16O + p interactions at 3.25A GeV/c was investigated with 4$\pi$ acceptance. The masses and widths of the resonances were obtained from an analysis of the experimental and background invariant-mass distributions of p$\pi^{{\pm}}_{}$ pairs. The fractions of charged pions coming from $\Delta^{{++}}_{}$ and $\Delta^{0}_{}$ decay were estimated. The momentum, kinetic energy, and emission angle distributions of $\Delta^{{++}}_{}$ and $\Delta^{0}_{}$ resonances were reconstructed in the oxygen nucleus rest frame. The slope parameters, T0 , of the reconstructed spectra of invariant cross-sections of $\Delta^{{++}}_{}$ and $\Delta^{0}_{}$ resonances, produced on oxygen nuclei in 16O + p interactions at 3.25A GeV/c , were determined