MARFE phenomena in the HT-7 tokamak

Citation
X. Gao et al., MARFE phenomena in the HT-7 tokamak, J NUCL MAT, 279(2-3), 2000, pp. 330-334
Citations number
13
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Nuclear Emgineering
Journal title
JOURNAL OF NUCLEAR MATERIALS
ISSN journal
0022-3115 → ACNP
Volume
279
Issue
2-3
Year of publication
2000
Pages
330 - 334
Database
ISI
SICI code
0022-3115(200006)279:2-3<330:MPITHT>2.0.ZU;2-6
Abstract
Multifaceted asymmetric radiation from the edge (MARFE) phenomena on the HT -7 superconducting tokamak are summarized in this paper. The best correlati on has been found between the total input ohmic power and the product of th e edge line average density and Z(eff). The occurrence of MARFEs are strong ly correlated with impurity density, and always occur at Z(eff) =3-8 ohmic discharges. In the HT-7 tokamak high Z(eff) discharges, it is found that th e MARFEs usually occur at values of Z(eff)(1/2)rho in the range of 0.5-0.7, where rho = pi a(2)n(e)/I-p (10(20) MA(-1) m(-1)). In the case of good wal l condition (Z(eff) = 1-2), the onset of MARFEs have not been observed befo re reaching the Greenwald density limit on the HT-7. Improved confinement m ode induced by a MARFE is observed, and it is maintained for about 40 ms. M ARFE cools the plasma edge, and the electron density profile is observed to become more narrow and peaked. (C) 2000 Elsevier Science B.V. All rights r eserved.