| Title: |
The low frequency edge oscillation in alcator C-Mod and ASDEX upgrade I-mode |
| Authors: |
McCarthy, W; Hubbard, A E; Terry, J; Labombard, B; Kuang, A; Bielajew, R; Hutchinson, I; Hughes, J W; Silvagni, D; Happel, T; Gil, L |
| Contributors: |
U.S. Nuclear Regulatory Commission; EUROfusion; Fusion Energy Sciences |
| Source: |
Plasma Physics and Controlled Fusion ; volume 67, issue 4, page 045014 ; ISSN 0741-3335 1361-6587 |
| Publisher Information: |
IOP Publishing |
| Publication Year: |
2025 |
| Description: |
The low frequency edge oscillation (LFEO) is a low frequency fluctuation in many plasma quantities in the pedestal region of the I-Mode confinement regime. It is observed on Alcator C-Mod between 10–30 kHz and on ASDEX Upgrade between 5–10 kHz. On both tokamaks it has been previously identified as a geodesic acoustic mode (GAM), however the recent discovery of the edge temperature ring oscillation (ETRO) in a similar frequency and spatial location as the LFEO in I-Modes on EAST has called this identification into question. In this paper we investigate the LFEO on C-Mod and AUG using a variety of different experimental techniques including spectral analysis, magnetic mode number analysis, localization, and direct measurement of the LFEO zonal structure and propagation using a mirror Langmuir probe. This investigation has reconfirmed the identification of the LFEO as a GAM and determined that it has several key differences from the ETRO. |
| Document Type: |
article in journal/newspaper |
| Language: |
unknown |
| DOI: |
10.1088/1361-6587/adbc1e |
| DOI: |
10.1088/1361-6587/adbc1e/pdf |
| Availability: |
https://doi.org/10.1088/1361-6587/adbc1e; https://iopscience.iop.org/article/10.1088/1361-6587/adbc1e; https://iopscience.iop.org/article/10.1088/1361-6587/adbc1e/pdf |
| Rights: |
https://creativecommons.org/licenses/by/4.0/ ; https://iopscience.iop.org/info/page/text-and-data-mining |
| Accession Number: |
edsbas.9B875896 |
| Database: |
BASE |