# Centrality Dependent Lévy-Stable Two-Pion Bose-Einstein Correlations in \( {\sqrt{s_{NN}}} \) = 200 GeV Au+Au Collisions at the PHENIX Experiment

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## Abstract

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## 1. Introduction

## 2. PHENIX Experiment

## 3. Two-Particle Correlation Functions and the Lévy Distribution

## 4. Results of the Centrality Dependent Analysis

#### 4.1. The Lévy Shape Parameter $\alpha $

#### 4.2. The Lévy Scale Parameter R

#### 4.3. The Lévy Strength $\lambda $

#### 4.4. New Scaling Parameter

## 5. Conclusions

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**A schematic beam view drawing of the detector system of the accelerator complex at the PHENIX experiment and the RHIC facilities from a bird’s-eye view.

**Figure 2.**Comparison of the Gaussian and the Lévy distribution with a given $\alpha $, R and $\lambda $. It can be seen that the Lévy distribution has a power-law-like tail.

**Figure 3.**The $\alpha $ Lévy stability parameter as a function of ${m}_{\mathrm{T}}$ (

**left**); The $\langle \alpha \rangle $ as a function of ${N}_{\mathrm{part}}$ (

**right**). The statistical errors are shown with errorbars and the systematical uncertainties boxes.

**Figure 4.**The Lévy scale parameter as a function of ${m}_{\mathrm{T}}$ with free $\alpha $ (

**left**) and in the case when $\alpha =\langle \alpha \rangle $ is fixed during the fit (

**right**). The statistical errors are shown with errorbars and the systematical uncertainties boxes.

**Figure 5.**The hydro-type behavior of the Lévy scale parameter as a function of ${m}_{\mathrm{T}}$ with free $\alpha $ (

**left**) and in the case when $\alpha =\langle \alpha \rangle $ is fixed during the fit (

**right**). The statistical errors are shown with errorbars and the systematical uncertainties boxes.

**Figure 6.**The $\lambda \left({m}_{\mathrm{T}}\right)$ function in the different centrality ranges (

**left**); The normalized $\lambda \left({m}_{\mathrm{T}}\right)$ function with fixed $\alpha =\langle \alpha \rangle $ value (

**right**). The statistical errors are shown with errorbars and the systematical uncertainties boxes.

**Figure 7.**The new, empirically found scaling variable does not depend on the $\alpha $ fixation. The statistical errors are shown with errorbars and the systematical uncertainties boxes.

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**MDPI and ACS Style**

Lökös, S.
Centrality Dependent Lévy-Stable Two-Pion Bose-Einstein Correlations in \( {\sqrt{s_{NN}}} \) = 200 GeV Au+Au Collisions at the PHENIX Experiment. *Universe* **2018**, *4*, 31.
https://doi.org/10.3390/universe4020031

**AMA Style**

Lökös S.
Centrality Dependent Lévy-Stable Two-Pion Bose-Einstein Correlations in \( {\sqrt{s_{NN}}} \) = 200 GeV Au+Au Collisions at the PHENIX Experiment. *Universe*. 2018; 4(2):31.
https://doi.org/10.3390/universe4020031

**Chicago/Turabian Style**

Lökös, Sándor.
2018. "Centrality Dependent Lévy-Stable Two-Pion Bose-Einstein Correlations in \( {\sqrt{s_{NN}}} \) = 200 GeV Au+Au Collisions at the PHENIX Experiment" *Universe* 4, no. 2: 31.
https://doi.org/10.3390/universe4020031