Collective and fractal properties of pion jets in the four-velocity space at intermediate energies

TL;DR

This study investigates the collective and fractal properties of pion jets in four-velocity space at intermediate energies, revealing energy-dependent behaviors and evidence for color degrees of freedom in pion jet production.

Contribution

It introduces experimental analysis of fractal and collective properties of pion jets at intermediate energies, highlighting energy-dependent changes and estimating the onset of color degrees of freedom.

Findings

Decreased mean square of particle distances from jet axis at ~3 GeV

Power dependence of distance on collision energy between 2-4 GeV

Fractal-like properties indicated by fractional cluster dimensions

Abstract

Experimental results are presented for study of collective and fractal properties of soft pion jets in the space of relative four-dimensional velocities. Significant decreasing is obtained for mean square of second particle distances from jet axis for pion-proton interactions at initial energies $\sim 3$ GeV in comparison with hadron-nuclear collisions at close energies. The decreasing results in power dependence of distance variable on collision energy for range $\sim 2 - 4$ GeV. The observation allows us to estimate the low boundary of manifestation of color degree of freedom in pion jet production. Cluster dimension values were deduced for pion jets in various reactions. Fractional values of this dimension indicate on the manifestation of fractal-like properties by pion jets. Changing of mean kinetic energy of jet particles and fractal dimension with initial energy increasing is consistent with suggestion for presence of color degrees of freedom in pion jet production at intermediate energies.