### Abstract

Original language | English |
---|---|

Pages (from-to) | 72308 |

Journal | Physics of Plasmas |

Volume | 21 |

Issue number | 7 |

DOIs | |

Publication status | Published - Jul 2014 |

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### Bibliographical note

The full text is available free from the link given. The published version can be found at http://dx.doi.org/10.1063/1.4890127 .### Keywords

- plasma physics
- ion temperature gradient mode
- energy transfer
- free energy
- plasma gyrokinetics
- electrostatics

### Cite this

*Physics of Plasmas*,

*21*(7), 72308. https://doi.org/10.1063/1.4890127

**The energetic coupling of scales in gyrokinetic plasma turbulence.** / Teaca, Bogdan; Navarro, A.B.; Jenko, F.

Research output: Contribution to journal › Article

*Physics of Plasmas*, vol. 21, no. 7, pp. 72308. https://doi.org/10.1063/1.4890127

}

TY - JOUR

T1 - The energetic coupling of scales in gyrokinetic plasma turbulence

AU - Teaca, Bogdan

AU - Navarro, A.B.

AU - Jenko, F.

N1 - The full text is available free from the link given. The published version can be found at http://dx.doi.org/10.1063/1.4890127 .

PY - 2014/7

Y1 - 2014/7

N2 - In magnetized plasma turbulence, the couplings of perpendicular spatial scales that arise due to the nonlinear interactions are analyzed from the perspective of the free-energy exchanges. The plasmas considered here, with appropriate ion or electron adiabatic electro-neutrality responses, are described by the gyrokinetic formalism in a toroidal magnetic geometry. Turbulence develops due to the electrostatic fluctuations driven by temperature gradient instabilities, either ion temperature gradient (ITG) or electron temperature gradient (ETG). The analysis consists in decomposing the system into a series of scale structures, while accounting separately for contributions made by modes possessing special symmetries (e.g., the zonal flow modes). The interaction of these scales is analyzed using the energy transfer functions, including a forward and backward decomposition, scale fluxes, and locality functions. The comparison between the ITG and ETG cases shows that ETG turbulence has a more pronounced classical turbulent behavior, exhibiting a stronger energy cascade, with implications for gyrokinetic turbulence modeling.

AB - In magnetized plasma turbulence, the couplings of perpendicular spatial scales that arise due to the nonlinear interactions are analyzed from the perspective of the free-energy exchanges. The plasmas considered here, with appropriate ion or electron adiabatic electro-neutrality responses, are described by the gyrokinetic formalism in a toroidal magnetic geometry. Turbulence develops due to the electrostatic fluctuations driven by temperature gradient instabilities, either ion temperature gradient (ITG) or electron temperature gradient (ETG). The analysis consists in decomposing the system into a series of scale structures, while accounting separately for contributions made by modes possessing special symmetries (e.g., the zonal flow modes). The interaction of these scales is analyzed using the energy transfer functions, including a forward and backward decomposition, scale fluxes, and locality functions. The comparison between the ITG and ETG cases shows that ETG turbulence has a more pronounced classical turbulent behavior, exhibiting a stronger energy cascade, with implications for gyrokinetic turbulence modeling.

KW - plasma physics

KW - ion temperature gradient mode

KW - energy transfer

KW - free energy

KW - plasma gyrokinetics

KW - electrostatics

U2 - 10.1063/1.4890127

DO - 10.1063/1.4890127

M3 - Article

VL - 21

SP - 72308

JO - Physics of Plasmas

JF - Physics of Plasmas

SN - 1070-664X

IS - 7

ER -