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Tokamak Plasmas: A Paradigm for Coronal Equilibrium and Disequilibrium

Published online by Cambridge University Press:  12 April 2016

Richard D. Petrasso*
Affiliation:
Plasma Fusion Center, MIT, Cambridge, MA 02139

Abstract

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Tokamaks operate over a wide parameter space, allowing access to plasma conditions relevant to astrophysical plasmas. For high electron density discharges, for example, the central electron density and temperature are ~ 3 × 1014cm-3 and ~ 1.5 keV, and the central plasma region is in coronal equilibrium. Towards the edge of the plasma, however, many ion species will be far out of coronal equilibrium. A novel feature of the edge region is the seemingly contradictory property that it is, simultaneously, both a strongly recombining and a strongly ionizing plasma. Recent tokamak observations of strongly recombining plasmas also show that the G parameter (the ratio of forbidden plus intercombination to resonance lines) is larger by a factor of 3 than the ratio of statistical weights of the triplet-singlet series. Such observations can be of direct consequence to the interpretation of non-equilibrium astrophysical plasmas.

Type
1. X-rays from a Hot Plasma
Copyright
Copyright © Cambridge University Press 1990

References

Artsimovich, L.A. 1972, Nuclear Fusion 6, 215.CrossRefGoogle Scholar
Bitter, M., Hill, K.W., Zarnstorff, S., von Goeler, S., Hulse, R., Johnson, L.C., Sauthoff, N.R., Sesnic, S., and Young, K.M. 1985, Phys.Rev.A 32(5), 3011.Google Scholar
Canizares, C.R., Winkler, P.F., Markert, T.H., and Berg, C. 1983, in Supernova Remnants and their X-ray Emission, Danziger, J. and Gorenstein, P. (eds.), IAU., 205.Google Scholar
Canizares, C.R. 1988, IAU Colloquium 115 (this conference), Gorenstein, P. and Zombeck, M. (eds).Google Scholar
Greenwald, M., Gwinn, D., Milora, S., Parker, J., Parker, R., Wolfe, S., Besen, B., Camacho, F., Fairfax, S., Fiore, C., Foord, M., Gandy, R., Gomez, C., Granetz, R., LaBombard, B., Lipschultz, B., Lloyd, B., Marmar, E., McCool, S., Pappas, D., Petrasso, R., Pribyl, P., Rice, J., Schuresko, D., Takase, Y., Terry, J., and Watterson, R. 1984, Phys.Rev.Lett. 53(4) 352.Google Scholar
Kallne, E., Kallne, J., Dalgarno, A., Marmar, E.S., Rice, J.E., and Pradhan, A.K. 1984, Phys.Rev.Lett. 52, 2245.CrossRefGoogle Scholar
Jordan, C. and Veck, N.J. 1982, Solar Phys. 78, 125.Google Scholar
Mason, H. 1988, IAU Colloquium 115 (this conference), Gorenstein, P. and Zombeck, M. (eds.).Google Scholar
Nuclear Fusion 25(9), 1985; this volume contains several articles on tokamak programs throughout the world.Google Scholar
Parker, R., Greenwald, M., Luckhardt, M., Marmar, E.S., Porkolab, M., and Wolfe, S.M. 1985, Nuclear Fusion 25(9), 1127; references therein.Google Scholar
Petrasso, R.D., Seguin, F.H., Loter, N.G., Marmar, E., and Rice, J. 1982, Phys.Rev.Lett. 49, 1826.Google Scholar
Rice, J.E., Marmar, E.S., Kallne, E., and Kallne, J. 1987, Phys.Rev. A 35(7), 3033; references therein.Google Scholar