# Non-Gaussian elliptic-flow fluctuations in PbPb collisions at $$\sqrt{\smash[b]{s_{_\text{NN}}}} = 5.02$$ TeV

## Abstract

Event-by-event fluctuations in the elliptic-flow coefficient $$v_2$$ are studied in PbPb collisions at $$\sqrt{s_{_\text{NN}}} = 5.02$$ TeV using the CMS detector at the CERN LHC. Elliptic-flow probability distributions $${p}(v_2)$$ for charged particles with transverse momentum 0.3$$< p_\mathrm{T} <$$3.0 GeV and pseudorapidity $$| \eta | <$$ 1.0 are determined for different collision centrality classes. The moments of the $${p}(v_2)$$ distributions are used to calculate the $$v_{2}$$ coefficients based on cumulant orders 2, 4, 6, and 8. A rank ordering of the higher-order cumulant results and nonzero standardized skewness values obtained for the $${p}(v_2)$$ distributions indicate non-Gaussian initial-state fluctuation behavior. Bessel-Gaussian and elliptic power fits to the flow distributions are studied to characterize the initial-state spatial anisotropy.

- Authors:

- Publication Date:

- Research Org.:
- Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

- Sponsoring Org.:
- USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)

- Contributing Org.:
- CMS

- OSTI Identifier:
- 1409852

- Report Number(s):
- FERMILAB-PUB-17-550-CMS; CMS-HIN-16-019; CERN-EP-2017-268; arXiv:1711.05594

1636197

- DOE Contract Number:
- AC02-07CH11359

- Resource Type:
- Journal Article

- Resource Relation:
- Journal Name: TBD

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

### Citation Formats

```
Sirunyan, Albert M, and et al.
```*Non-Gaussian elliptic-flow fluctuations in PbPb collisions at $\sqrt{\smash[b]{s_{_\text{NN}}}} = 5.02$ TeV*. United States: N. p., 2017.
Web.

```
Sirunyan, Albert M, & et al.
```*Non-Gaussian elliptic-flow fluctuations in PbPb collisions at $\sqrt{\smash[b]{s_{_\text{NN}}}} = 5.02$ TeV*. United States.

```
Sirunyan, Albert M, and et al. Wed .
"Non-Gaussian elliptic-flow fluctuations in PbPb collisions at $\sqrt{\smash[b]{s_{_\text{NN}}}} = 5.02$ TeV". United States.
doi:. https://www.osti.gov/servlets/purl/1409852.
```

```
@article{osti_1409852,
```

title = {Non-Gaussian elliptic-flow fluctuations in PbPb collisions at $\sqrt{\smash[b]{s_{_\text{NN}}}} = 5.02$ TeV},

author = {Sirunyan, Albert M and et al.},

abstractNote = {Event-by-event fluctuations in the elliptic-flow coefficient $v_2$ are studied in PbPb collisions at $\sqrt{s_{_\text{NN}}} = 5.02$ TeV using the CMS detector at the CERN LHC. Elliptic-flow probability distributions ${p}(v_2)$ for charged particles with transverse momentum 0.3$< p_\mathrm{T} <$3.0 GeV and pseudorapidity $| \eta | <$ 1.0 are determined for different collision centrality classes. The moments of the ${p}(v_2)$ distributions are used to calculate the $v_{2}$ coefficients based on cumulant orders 2, 4, 6, and 8. A rank ordering of the higher-order cumulant results and nonzero standardized skewness values obtained for the ${p}(v_2)$ distributions indicate non-Gaussian initial-state fluctuation behavior. Bessel-Gaussian and elliptic power fits to the flow distributions are studied to characterize the initial-state spatial anisotropy.},

doi = {},

journal = {TBD},

number = ,

volume = ,

place = {United States},

year = {Wed Nov 15 00:00:00 EST 2017},

month = {Wed Nov 15 00:00:00 EST 2017}

}