Measurement and modelling of suprathermal electron bursts generated in front of a lower hybrid antenna

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389021%3A_____%2F16%3A00459865" target="_blank" >RIV/61389021:_____/16:00459865 - isvavai.cz</a>

Result on the web

<a href="http://dx.doi.org/10.1088/0029-5515/56/3/036004" target="_blank" >http://dx.doi.org/10.1088/0029-5515/56/3/036004</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/0029-5515/56/3/036004" target="_blank" >10.1088/0029-5515/56/3/036004</a>

Result language

angličtina

Original language name

Measurement and modelling of suprathermal electron bursts generated in front of a lower hybrid antenna

Original language description

Measurements in the tokamak scrape-off layer show the existence of fast electrons as far as a few centimeters radially in front of a lower hybrid antenna grill, which is one order of magnitude further than earlier predictions of interaction zones not exceeding 5 mm in width (Rantamaki et al 2000 Nucl. Fusion 40 1477). The present contribution aims at understanding these experimental results on the basis of electron Landau damping in a turbulent scrape-off layer. A crucial guiding element from the experiments is the observation of temporal intermittency of the fast electron signal at positions radially away from the grill mouth at a rate comparable with the detachment rate of relatively hot and dense field-aligned plasma filaments, or 'blobs,' from the last closed flux surface. When the dynamic character of the scrape-off layer is taken into account, transient low density and low temperature states occur during which the Landau damping can be weak enough to allow the radiated spectrum to penetrate radially deep inward. When the lower hybrid wave intercepts a dense and hot 'blob' a few cm in front of the antenna, then strong damping of the high wave number components can occur. This is the scenario we propose for explaining the generation of fast electrons far away from the grill mouth.

Czech name

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Czech description

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Type

J_x - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)

CEP classification

BL - Plasma physics and discharge through gases

OECD FORD branch

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Project

<a href="/en/project/LM2011021" target="_blank" >LM2011021: COMPASS-RI - Contribution to operation and baseline human resources of the COMPASS tokamak - a large research infrastructure of European impact</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2016

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Nuclear Fusion

ISSN

0029-5515

e-ISSN

—

Volume of the periodical

56

Issue of the periodical within the volume

3

Country of publishing house

AT - AUSTRIA

Number of pages

21

Pages from-to

036004

UT code for WoS article

000373378200005

EID of the result in the Scopus database

2-s2.0-84960404729