In this work, we present a bag-type model within a nonextensive statistics applied to the description of the properties of a hadronic system with an underlying fractal structure. The nonextensive ideal gas inside the bag is determined by the grand canonical partition function from which pressure, energy, and particle density, as well as temperature and chemical potential are obtained for the hadronic system. These quantities are studied in the approximation of fixed mass for all bag constituents but also for discrete and continuum masses. In all cases, the freeze-out line, corresponding to the energy per particle equal to 1 GeV, and the lines corresponding to a fractal structure inside the proton volume are obtained. Finally, the pressure on the bag surface of the proton is calculated and the resulting value $(0.135\mathrm{GeV}{)}^4$ is obtained.

• Received 26 July 2019
• Revised 13 February 2020
• Accepted 18 February 2020

DOI:https://doi.org/10.1103/PhysRevD.101.054022