@article{99028fe92d1c4d3295c88a205562c27f,
title = "Three-dimensional inhomogeneity of electron-temperature-gradient turbulence in the edge of tokamak plasmas",
abstract = "Nonlinear multiscale gyrokinetic simulations of a Joint European Torus edge pedestal are used to show that electron-temperature-gradient (ETG) turbulence has a rich three-dimensional structure, varying strongly according to the local magnetic-field configuration. In the plane normal to the magnetic field, the steep pedestal electron temperature gradient gives rise to anisotropic turbulence with a radial (normal) wavelength much shorter than in the binormal direction. In the parallel direction, the location and parallel extent of the turbulence are determined by the variation in the magnetic drifts and finite-Larmor-radius (FLR) effects. The magnetic drift and FLR topographies have a perpendicular-wavelength dependence, which permits turbulence intensity maxima near the flux-surface top and bottom at longer binormal scales, but constrains turbulence to the outboard midplane at shorter electron-gyroradius binormal scales. Our simulations show that long-wavelength ETG turbulence does not transport heat efficiently, and significantly decreases overall ETG transport-in our case by ∼40%-through multiscale interactions.",
keywords = "electron-temperature-gradient instability, magnetic geometry, multiscale turbulence, pedestal turbulence, plasma turbulence, tokamaks, topography of turbulence",
author = "{JET Contributors} and Parisi, {J. F.} and Parra, {F. I.} and Roach, {C. M.} and Hardman, {M. R.} and Schekochihin, {A. A.} and Abel, {I. G.} and N. Aiba and J. Ball and M. Barnes and B. Chapman-Oplopoiou and D. Dickinson and W. Dorland and C. Giroud and Hatch, {D. R.} and Hillesheim, {J. C.} and {Ruiz Ruiz}, J. and S. Saarelma and D. St-Onge",
note = "Funding Information: We are grateful for stimulating conversations with T. Adkins, N. Christen, A. Field, W. Guttenfelder, G.W. Hammett, and M.J. Pueschel. JFP was supported by a Culham Fusion Research Fellowship. FIP, MRH, MB, AAS, DS, and DD were supported in part by the TDoTP project funded by EPSRC (Grant Number EP/R034737/1). This work was supported by the U.S. Department of Energy under Contract Number DE-AC02-09CH11466. The United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. This work has been carried out within the framework of the EUROfusion Consortium, funded by the European Union via the Euratom Research and Training Programme (Grant Agreement No. 101052200—EUROfusion). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Commission. Neither the European Union nor the European Commission can be held responsible for them. This work has been carried out within the framework of the Contract for the Operation of the JET Facilities and has received funding from the European Union{\textquoteright}s Horizon 2020 research and innovation programme. This work was performed using the Cambridge Service for Data Driven Discovery (CSD3), operated by the University of Cambridge Research Computing on behalf of the STFC DiRAC HPC Facility. The DiRAC component of CSD3 was funded by BEIS capital funding via STFC capital Grants ST/P002307/1 and ST/R002452/1 and STFC operations Grant ST/R00689X/1. This work was supported by the US Department of Energy through Grant DE-SC0018429. This work was carried out using the JFRS-1 supercomputer system at Computational Simulation Centre of International Fusion Energy Research Centre (IFERC-CSC) in Rokkasho Fusion Institute of QST (Aomori, Japan). Publisher Copyright: {\textcopyright} 2022 IAEA, Vienna.",
year = "2022",
month = aug,
doi = "10.1088/1741-4326/ac786b",
language = "English (US)",
volume = "62",
journal = "Nuclear Fusion",
issn = "0029-5515",
publisher = "IOP Publishing Ltd.",
number = "8",
}