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Fractal Entropy of Nuclear Medium Probed by ${K}_{S}^{0}$ Mesons Produced in AuAu Collisions at RHIC

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## Abstract

**:**

## 1. Introduction

## 2. Concept of $\mathbf{z}$-Scaling

## 3. Fractal Entropy ${\mathbf{S}}_{\mathbf{\delta},\mathbf{\u03f5}}$

## 4. Anomalous Behavior of the Fractal Entropy

## 5. Self-Similarity of ${\mathit{K}}_{\mathit{S}}^{\mathbf{0}}$ Production

## 6. Discussion

## Author Contributions

## Funding

## Data Availability Statement

## Conflicts of Interest

## References

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**Figure 1.**The dependence of the entropy (5) on the nucleon-nucleon center-of-mass, energy $\sqrt{{s}_{NN}}$, for ${K}_{S}^{0}$-meson transverse momentum ${p}_{T}=$ 0.3, 0.7, 1.0, 1.5, 2.0, and 3.0 GeV/c in the 0–5% (most central) (

**a**) and 60–80% (most peripheral) (

**b**) AuAu collisions in the rapidity interval $\left|y\right|<0.5$. Figures are taken from Ref. [30].

**Figure 2.**The scaling function $\psi \left(z\right)$ for ${K}_{S}^{0}$ mesons produced in the 0–5% (most central) AuAu collisions at $\sqrt{{s}_{NN}}=7.7$, 11.5, 19.6, 27, 39, 62.4, and 200 GeV in the rapidity range $\left|y\right|<0.5$. The symbols correspond to the data [22,23,25] of the Beam Energy Scan (BES) program by the STAR Collaboration at RHIC. The solid line is a reference curve for pp collisions [27]. Figure is taken from Ref. [30].

**Figure 3.**The nucleon structural dimension $\delta $ (

**a**) and the specific heat parameter ${c}_{\mathrm{AA}}$ (

**b**) for ${K}_{S}^{0}$-meson production in AuAu collisions in dependence on the collision energy at $\left|y\right|<0.5$. Figures are taken from Ref. [30].

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**MDPI and ACS Style**

Tokarev, M.; Zborovský, I.
Fractal Entropy of Nuclear Medium Probed by *Physics* **2023**, *5*, 537-546.
https://doi.org/10.3390/physics5020038

**AMA Style**

Tokarev M, Zborovský I.
Fractal Entropy of Nuclear Medium Probed by *Physics*. 2023; 5(2):537-546.
https://doi.org/10.3390/physics5020038

**Chicago/Turabian Style**

Tokarev, Mikhail, and Imrich Zborovský.
2023. "Fractal Entropy of Nuclear Medium Probed by *Physics* 5, no. 2: 537-546.
https://doi.org/10.3390/physics5020038