# Structure of the Medium Formed in Heavy Ion Collisions

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## Abstract

**:**

## 1. Introduction

## 2. Models

#### 2.1. Color String Percolation Model

#### 2.2. Core–Shell-Color String Percolation Model

#### 2.3. Color Glass Condensate

## 3. Simulation Methods and Data Analysis

#### 3.1. Color String Percolation Model

#### 3.2. Core–Shell-Color String Percolation Model

#### 3.3. Color Glass Condensate

## 4. Discussion and Conclusions

## Author Contributions

## Funding

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 2.**Samples of systems for the CSCSPM along with their corresponding radial distribution function. Note that in (

**b.2**) and (

**b.3**), we observe a transition from non-ideal gas to liquid-like structures.

**Figure 3.**Sample of a system that shows a liquid-like structure together with the spanning cluster (blue circles). This occurs with a difference in transition temperatures (configurational and geometric) lower than 1 MeV.

**Figure 4.**(

**a**) Probability density function of ${Q}_{S}$. (

**b**) Sample of ${\alpha}_{s}$-values as a function of ${Q}_{s}$. (

**c**) Probability density function of ${\alpha}_{s}$ of the systems under study: AuAu at $\sqrt{s}=$ 130 GeV (green lines and circles), AuAu at $\sqrt{s}=$ 200 GeV (blue lines and triangles), PbPb $\sqrt{s}=$ 2760 GeV (magenta lines and stars), and PbPb $\sqrt{s}=$ 5020 GeV (yellow lines and crosses).

**Figure 5.**Probability density function for (

**a**) the gluon density and (

**b**) the minimum distances between gluon centers.

**Figure 6.**Used histograms for simulation (

**a**) the number of gluons in the square and (

**b**) classes of minimum distances among gluons normalized by the average diameter of a gluon.

**Figure 7.**Samples of generated systems in the picture of the CGC after the thermalization for (

**a**) AuAu collisions at $\sqrt{s}=$ 130 GeV, (

**b**) AuAu collisions at $\sqrt{s}=$ 200 GeV, (

**c**) PbPb collisions at $\sqrt{s}=$ 2760 GeV, and (

**d**) PbPb collisions at $\sqrt{s}=$ 5020 GeV. These systems correspond to a square box of around 1fm${}^{2}$. The inner dashed square is the size of the simulated system for the purposes of the computation of the radial distribution function.

**Figure 8.**Radial distribution function of systems in the picture of the CGC for (

**a**) AuAu collisions at $\sqrt{s}=$ 130 GeV, (

**b**) AuAu collisions at $\sqrt{s}=$ 200 GeV, (

**c**) PbPb collisions at $\sqrt{s}=$ 2760 GeV, and (

**d**) PbPb collisions at $\sqrt{s}=$ 5020 GeV. The inner plots correspond to the percentage of deviation of the radial distribution function from the one obtained for AuAu collisions at $\sqrt{s}=$ 130 GeV.

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**MDPI and ACS Style**

Alvarado García, J.R.; Rosales Herrera, D.; Fernández Téllez, A.; Díaz, B.; Ramírez, J.E.
Structure of the Medium Formed in Heavy Ion Collisions. *Universe* **2023**, *9*, 291.
https://doi.org/10.3390/universe9060291

**AMA Style**

Alvarado García JR, Rosales Herrera D, Fernández Téllez A, Díaz B, Ramírez JE.
Structure of the Medium Formed in Heavy Ion Collisions. *Universe*. 2023; 9(6):291.
https://doi.org/10.3390/universe9060291

**Chicago/Turabian Style**

Alvarado García, J. R., D. Rosales Herrera, A. Fernández Téllez, Bogar Díaz, and J. E. Ramírez.
2023. "Structure of the Medium Formed in Heavy Ion Collisions" *Universe* 9, no. 6: 291.
https://doi.org/10.3390/universe9060291