L. Popova

Connection between the statistical parameters of hadronization and the QCD coupling constant

We propose a statistical parameterization of hadron production which is verified up to the highest EAS energies. This parameterization leads to Stephan’s type equation of state relating the ‘temperature’ of the relativistic hadron gas with the collision energy if a power multiplicity law is assumed. A correspondence between the lattice theory expansion on the coupling constant and the statistical sum of temperature expansion in statistical mechanics reveals a simple relation between the multiplicity power law index and the coupling constant. Cosmic ray data yield estimates of the running values of the coupling constant beyond the range of collider experiments. These estimates indicate the asymptotic behavior of the running values of the coupling constant and provide a hint that color confinement and asymptotic freedom of quarks co exist in an unified phase of QCD.

Semi-inclusive model for high-energy interactions

A detailed phenomenological model for high-energy interactions is developed on the basis of the semi-inclusive cross sections from accelerator experiments. The model is extrapolated to EAS energies by assuming the validity of statistical scaling. The calculated characteristics of showers for proton and for iron primaries are compared with experimental data at mountain altitudes. There is a general agreement between the model predictions and EAS data.

Muons in extensive air showers at mountain altitudes

Experimental data on muons in extensive air showers at mountain altitude have been compared with numerical calculations based on a variety of high-energy collision models. It has been found that the data in general show the same features as those concerning muons in EAS registered at sea level, namely they also indicate rapid development of showers. It is pointed out that it becomes difficult to explain simultaneously the sea-level and mountain-altitude data on muons under the assumption that the scaling model of interactions is valid even if very heavy nuclei dominate in the primary flux.

Do we observe a change in multihadron production

We have parametrized collider data in terms of a thermodynamical model for hadron interactions. This model was adopted for higher cosmic ray energies. The calculated characteristics EAS are compared with different experimental data. No evidence for a change of particle interactions is found.

Violation of KNO scaling

Assuming Feynman scaling of secondary hadron spectra Koba, Nielsen and Olesen have derived energy invariance of relative multiplicity distribution. We have derived a violated KNO scaling when statistical invariance of hadron momentum spectra is assumed. It is in reasonable agreement with collider data at high energies. The observed behaviour of multiplicity distributions could confirm the hypothesis for a smooth transition from color confined phase to asymptotically free hadronization matter.

A cascade generator based on the quark‐gluon string model

A computer generator for simulation of hadron cascades in the atmosphere is developed on the basis of the quark‐gluon string model. Preliminary results that can be used for interpretation of emulsion chamber are presented.