### Abstract

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.

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

Pages (from-to) | 72308 |

Journal | Physics of Plasmas |

Volume | 21 |

Issue number | 7 |

DOIs | |

Publication status | Published - Jul 2014 |

### 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

## Fingerprint Dive into the research topics of 'The energetic coupling of scales in gyrokinetic plasma turbulence'. Together they form a unique fingerprint.

## Cite this

Teaca, B., Navarro, A. B., & Jenko, F. (2014). The energetic coupling of scales in gyrokinetic plasma turbulence.

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