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Centrality-Dependent Lévy HBT Analysis in $\sqrt{{\mathit{s}}_{{}_{\mathbf{NN}}}}\mathbf{=}\mathbf{5.02}$ TeV PbPb Collisions at CMS

## Abstract

**:**

## 1. Introduction

## 2. Femtoscopy with Lévy Sources

## 3. Measurement Details

## 4. Results and Discussion

## 5. Conclusions

## Funding

## Data Availability Statement

## Conflicts of Interest

## Abbreviations

QGP | quark–gluon plasma |

LHC | Large Hadron Collider |

HBT | Hanbury Brown and Twiss |

PbPb | lead–lead |

CMS | Compact Muon Solenoid |

AuAu | gold–gold |

## Appendix A. Results for Negatively Charged Pairs

**Figure A1.**The Lévy stability index $\alpha $ versus the transverse mass ${m}_{\mathrm{T}}$ in different centrality classes for negatively charged hadron pairs [41]. The error bars are the statistical uncertainties, while the boxes indicate the uncorrelated systematic uncertainties. The correlated systematic uncertainty is shown in the legend.

**Figure A2.**The Lévy scale parameter R versus ${m}_{\mathrm{T}}$ in different centrality classes for negatively charged hadron pairs [41]. The error bars are the statistical uncertainties, while the boxes indicate the uncorrelated systematic uncertainties. The correlated systematic uncertainty is shown in the legend.

**Figure A3.**The inverse square of the Lévy scale parameter R versus ${m}_{\mathrm{T}}$ in different centrality classes for negatively charged hadron pairs [41]. The error bars are the statistical uncertainties, while the boxes indicate the uncorrelated systematic uncertainties. The correlated systematic uncertainty is shown in the legend. A line is fitted to the data for each centrality.

**Figure A4.**The correlation strength $\lambda $ and the rescaled correlation strength ${\lambda}^{*}$ versus ${m}_{\mathrm{T}}$ in different centrality classes for negatively charged hadron pairs [41]. The error bars are the statistical uncertainties, while the boxes indicate the uncorrelated systematic uncertainties. The correlated systematic uncertainty is shown in the legend.

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**Figure 1.**An example fit to the double-ratio correlation function $DR\left(q\right)$ of negatively charged hadrons [41]. The fitted function is shown in black, while the red overlay indicates the range used for the fit. The ${K}_{\mathrm{T}}$ and centrality class is shown in the legend. The lower panel indicates the deviation of the fit from the data.

**Figure 2.**The Lévy stability index $\alpha $ versus the transverse mass ${m}_{\mathrm{T}}$ in different centrality classes for positively charged hadron pairs [41]. The error bars are the statistical uncertainties, while the boxes indicate the uncorrelated systematic uncertainties. The correlated systematic uncertainty is shown in the legend.

**Figure 3.**The average Lévy stability index $\langle \alpha \rangle $ versus $\langle {N}_{\mathrm{part}}\rangle $ in different centrality classes for positively and negatively charged hadron pairs [41]. The error bars are the statistical uncertainties, while the boxes indicate the systematic uncertainties.

**Figure 4.**The Lévy scale parameter R versus ${m}_{\mathrm{T}}$ in different centrality classes for positively charged hadron pairs [41]. The error bars are the statistical uncertainties, while the boxes indicate the uncorrelated systematic uncertainties. The correlated systematic uncertainty is shown in the legend.

**Figure 5.**The inverse square of the Lévy scale parameter R versus ${m}_{\mathrm{T}}$ in different centrality classes for positively charged hadron pairs [41]. The error bars are the statistical uncertainties, while the boxes indicate the uncorrelated systematic uncertainties. The correlated systematic uncertainty is shown in the legend. A line is fitted to the data for each centrality.

**Figure 6.**The two fit parameters from the linear fit: the slope A (

**upper**) and the intercept B (

**lower**) versus $\langle {N}_{\mathrm{part}}\rangle $ for negatively and positively charged hadron pairs [41]. The error bars are the statistical uncertainties, while the boxes indicate the systematic uncertainties.

**Figure 7.**The correlation strength $\lambda $ and the rescaled correlation strength ${\lambda}^{*}$ versus ${m}_{\mathrm{T}}$ in different centrality classes for positively charged hadron pairs [41]. The error bars are the statistical uncertainties, while the boxes indicate the uncorrelated systematic uncertainties. The correlated systematic uncertainty is shown in the legend.

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**MDPI and ACS Style**

Kórodi, B., on behalf of the CMS Collaboration.
Centrality-Dependent Lévy HBT Analysis in *Universe* **2023**, *9*, 318.
https://doi.org/10.3390/universe9070318

**AMA Style**

Kórodi B on behalf of the CMS Collaboration.
Centrality-Dependent Lévy HBT Analysis in *Universe*. 2023; 9(7):318.
https://doi.org/10.3390/universe9070318

**Chicago/Turabian Style**

Kórodi, Balázs on behalf of the CMS Collaboration.
2023. "Centrality-Dependent Lévy HBT Analysis in *Universe* 9, no. 7: 318.
https://doi.org/10.3390/universe9070318