The results of treatment of data obtained in the SERP-E-184experiment Investigation of mechanisms of the production of charmed particles in proton-nucleus interactions at 70 GeV and their decays by irradiating the active target of the SVD-2 facility
consisting of carbon, silicon, and lead plates, are presented. After separating a signal from the two-particle decay of neutral charmed mesons and estimating the cross section for charm production at a threshold energy {sigma}(cv{c})=7.1 pm 2.4(stat.) pm 1.4(syst.) mub/nucleon, some properties of D mesons are investigated. These include the dependence of the cross section on the target mass number (its A dependence); the behavior of the differential cross sections d{sigma}/dpt2 and d{sigma}/dxF; and the dependence of the parameter {alpha} on the kinematical variables xF, pt2, and plab. The experimental results in question are compared with predictions obtained on the basis of the FRITIOF7.02 code.
Neutral pion number N0 distributions for each total number of particles in event Ntot=Nch+N0 are obtained. The scaled variance of neutral pion fluctuations, omega=D/<N0>, is measured. The fluctuations increase at Ntot >22. According to quantum statis
tics models it may indicate for the approaching to pion condensate conditions for high pion multiplicity in the system.
Project Thermalization (Experiment SERP-E-190 at IHEP) is aimed to study the proton - proton interactions at 50 GeV with large number of secondary particles. In this report the experimentally measured topological cross sections are presented taking i
nto account the detector response and procession efficiency. These data are in good agreement with gluon dominance model. The comparison with other models is also made and shows no essential discrepancies.
