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Influence of Spatial and Dynamical Anisotropies on Flow and Femtoscopy Radii in Relativistic Heavy-Ion Collisions at LHC Energies^{ †}

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^{2}

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^{†}

## Abstract

**:**

## 1. Introduction

## 2. HYDJET++ Model

## 3. Results of the Simultaneous Description of ${v}_{2}$, ${v}_{3}$, and Oscillations of Femtoscopic Radii

## 4. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**(

**a**–

**c**) The azimuthal dependence of ${R}_{side}^{2}\left(\Delta {\varphi}_{2}\right)$, ${R}_{out}^{2}\left(\Delta {\varphi}_{2}\right)$, and ${R}_{long}^{2}\left(\Delta {\varphi}_{2}\right)$, respectively, in the HYDrodynamics with JETs (HYDJET++) calculations of Pb + Pb collisions at $\sqrt{s}=2.76$ GeV with the centrality 20–30%. The ${k}_{T}$ range is 0.2–2.0 GeV/c. (

**d**) The differential elliptic flow of charged hadrons as a function of ${p}_{T}$. The distributions show calculations with ${\epsilon}_{2}=0.3$ (solid circles) and with ${\epsilon}_{2}=-0.3$ (open circles). ALICE data from [13] for $0.5<{k}_{T}<0.7$ GeV/c are shown by crosses. Lines are drawn to guide the eye.

**Figure 2.**The same as Figure 1, but for calculations with ${\delta}_{2}=0.3$ (solid circles) and with ${\delta}_{2}=-0.3$ (open circles).

**Figure 3.**(

**a**–

**c**) The azimuthal dependence of ${R}_{side}^{2}\left(\Delta {\varphi}_{3}\right)$, ${R}_{out}^{2}\left(\Delta {\varphi}_{3}\right)$, and ${R}_{long}^{2}\left(\Delta {\varphi}_{3}\right)$, respectively, in HYDJET++ calculations of Pb + Pb collisions at $\sqrt{s}=2.76$ GeV with the centrality 20–30%. The ${k}_{T}$ range is 0.2–2.0 GeV/c. (

**d**) The differential triangular flow of charged hadrons as a function of ${p}_{T}$. The distributions show calculations with ${\epsilon}_{3}=0.3$ (solid circles) and with ${\epsilon}_{3}=-0.3$ (open circles). Crosses denote the ALICE data for $0.5<{k}_{T}<0.7$ GeV/c from [14]. Lines are drawn to guide the eye.

**Figure 4.**The same as Figure 3, but for calculations with ${\rho}_{3}=0.3$ (solid circles) and with ${\rho}_{3}=-0.3$ (open circles).

**Figure 5.**Pion emission function in the transverse plane of HYDJET++ simulated Pb + Pb collisions at $\sqrt{s}=2.76$ TeV with centrality 20–30%. The left column displays calculations with only spatial elliptic anisotropy ${\epsilon}_{2}=0.5$, whereas the right column presents results for non-zero dynamical anisotropy ${\delta}_{2}=-0.3$. Shaded contours are identical for each column and indicate the density of emitted pions. Contour lines show the densities of pions emitted at angles $0<\varphi \le \pi /4$ (

**upper row**), $\pi /4<\varphi \le \pi /2$ (

**middle row**), and $\pi /2<\varphi \le 3\pi /4$ (

**bottom row**), respectively.

**Figure 6.**The same as Figure 5, but for calculations with non-zero geometric triangular anisotropy ${\epsilon}_{3}=0.3$ (

**left column**) and with non-zero dynamical triangular anisotropy ${\rho}_{3}=0.5$ (

**right column**). Contour lines show the densities of pions emitted at angles $0<\varphi \le \pi /6$ (

**upper row**), $\pi /3<\varphi \le \pi /2$ (

**middle row**), and $2\pi /3<\varphi \le 5\pi /6$ (

**bottom row**), respectively.

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**MDPI and ACS Style**

Zabrodin, E.E.; Bravina, L.V.; Lokhtin, I.P.; Malinina, L.V.; Petrushanko, S.V.; Snigirev, A.M.
Influence of Spatial and Dynamical Anisotropies on Flow and Femtoscopy Radii in Relativistic Heavy-Ion Collisions at LHC Energies. *Proceedings* **2019**, *13*, 3.
https://doi.org/10.3390/proceedings2019013003

**AMA Style**

Zabrodin EE, Bravina LV, Lokhtin IP, Malinina LV, Petrushanko SV, Snigirev AM.
Influence of Spatial and Dynamical Anisotropies on Flow and Femtoscopy Radii in Relativistic Heavy-Ion Collisions at LHC Energies. *Proceedings*. 2019; 13(1):3.
https://doi.org/10.3390/proceedings2019013003

**Chicago/Turabian Style**

Zabrodin, E. E., L. V. Bravina, I. P. Lokhtin, L. V. Malinina, S. V. Petrushanko, and A. M. Snigirev.
2019. "Influence of Spatial and Dynamical Anisotropies on Flow and Femtoscopy Radii in Relativistic Heavy-Ion Collisions at LHC Energies" *Proceedings* 13, no. 1: 3.
https://doi.org/10.3390/proceedings2019013003