# Azimuthal anisotropies at high momentum from purely non-hydrodynamic transport

## Abstract

In the limit of short mean free path, relativistic kinetic theory gives rise to hydrodynamics through a systematically improvable gradient expansion. In the present work, a systematically improvable expansion in the opposite limit of large mean free path is considered, describing the dynamics of particles which are almost, but not quite, non-interacting. This non-hydrodynamic “eremitic” expansion does not break down for large gradients, and may be useful in situations where a hydrodynamic treatment is not applicable. As applications, azimuthal anisotropies at high transverse momenta in Pb + Pb and p + Pb collisions at $$ \sqrt{s}$$ = 5.02 TeV are calculated from the first order eremitic expansion of kinetic theory in the relaxation time approximation.

- Authors:

- Publication Date:

- Research Org.:
- Univ. of Colorado, Boulder, CO (United States)

- Sponsoring Org.:
- USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)

- OSTI Identifier:
- 1463912

- Alternate Identifier(s):
- OSTI ID: 1510001

- Grant/Contract Number:
- SC0017905

- Resource Type:
- Published Article

- Journal Name:
- European Physical Journal. C, Particles and Fields

- Additional Journal Information:
- Journal Name: European Physical Journal. C, Particles and Fields Journal Volume: 78 Journal Issue: 8; Journal ID: ISSN 1434-6044

- Publisher:
- Springer Science + Business Media

- Country of Publication:
- Germany

- Language:
- English

- Subject:
- 73 NUCLEAR PHYSICS AND RADIATION PHYSICS

### Citation Formats

```
Romatschke, Paul. Azimuthal anisotropies at high momentum from purely non-hydrodynamic transport. Germany: N. p., 2018.
Web. doi:10.1140/epjc/s10052-018-6112-6.
```

```
Romatschke, Paul. Azimuthal anisotropies at high momentum from purely non-hydrodynamic transport. Germany. doi:10.1140/epjc/s10052-018-6112-6.
```

```
Romatschke, Paul. Fri .
"Azimuthal anisotropies at high momentum from purely non-hydrodynamic transport". Germany. doi:10.1140/epjc/s10052-018-6112-6.
```

```
@article{osti_1463912,
```

title = {Azimuthal anisotropies at high momentum from purely non-hydrodynamic transport},

author = {Romatschke, Paul},

abstractNote = {In the limit of short mean free path, relativistic kinetic theory gives rise to hydrodynamics through a systematically improvable gradient expansion. In the present work, a systematically improvable expansion in the opposite limit of large mean free path is considered, describing the dynamics of particles which are almost, but not quite, non-interacting. This non-hydrodynamic “eremitic” expansion does not break down for large gradients, and may be useful in situations where a hydrodynamic treatment is not applicable. As applications, azimuthal anisotropies at high transverse momenta in Pb + Pb and p + Pb collisions at $ \sqrt{s}$ = 5.02 TeV are calculated from the first order eremitic expansion of kinetic theory in the relaxation time approximation.},

doi = {10.1140/epjc/s10052-018-6112-6},

journal = {European Physical Journal. C, Particles and Fields},

number = 8,

volume = 78,

place = {Germany},

year = {2018},

month = {8}

}

DOI: 10.1140/epjc/s10052-018-6112-6

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Figures / Tables found in this record:

*Figures/Tables have been extracted from DOE-funded journal article accepted manuscripts.*