The Boundary Effect of QGP Droplet and Self-similarity Effect of Hadrons on QGP-hadron Phase Transition

TL;DR

This paper explores how boundary effects of QGP droplets and self-similarity structures of hadrons influence the QGP-hadron phase transition, affecting thermodynamic properties and transition temperature predictions.

Contribution

It introduces a modified MIT bag model with boundary effects and a Two-Body Fractal Model to study self-similarity, providing new insights into phase transition dynamics.

Findings

QGP energy, entropy, and pressure decrease due to boundary effects.

Self-similarity structures increase these thermodynamic quantities.

Model predicts higher transition temperatures considering both effects.

Abstract

We investigate the boundary effect of QGP droplet and self-similarity effect of hadrons on QGP-hadron phase transition. In intermediate or low energy collisions, when the transverse momentum is below QCD scale, QGP cannot be produced. However, if the transverse momentum fluctuates to a relatively large value, small scale QGP droplet is produced. The modified MIT bag model with multiple reflection expansion method is employed to study the QGP droplet with the curved boundary effect. It is found that the energy density, entropy density and pressure of QGP with the influence are smaller than those without the influence. In hadron phase, we propose Two-Body Fractal Model (TBFM) to study the self-similarity structure, arising from the resonance, quantum correlation and interaction effects. It is observed that energy density, entropy density and pressure increase due to the self-similarity structure. We calculate the transverse momentum spectra of pions with the self-similarity structure influence, showing a good agreement with the experimental data. Considering both the boundary effect and self-similarity structure influence, our model predicts an increase in the transition temperature compared to scenarios without these two effects in HIAF energy region $2.2\sim 4.5 \,\text{GeV}$.