Abstract
In JET limiter plasmas the density limit is associated with radiated power fractions of 100% and, in plasmas with carbon limiters, it is invariably disruptive. However, in discharges with solid beryllium limiters the limit is identified with the formation of a MARFE and disruptions are less frequent. In addition, the improved conditioning of the vessel arising from the use of beryllium has significantly improved the density limit scaling, so that the maximum density rises with the square root of the input power. In diverted plasmas several confinement regimes exist, making the characterization of the density limit more complex. While the density limit in L-mode plasmas is generally disruptive, the limit in ELMy and ELM-free H-modes generally prompts a return to the L-mode and a disruption is not inevitable. The density limit does rise with the increasing power, but the L-to-H transition complicates the analysis. Nevertheless, at low plasma currents (<2 MA), densities significantly above the Greenwald limit can be achieved, while at higher currents power handling limitations have constrained the range of density which can be achieved. (authors). 7 refs., 4 figs.
Campbell, D J;
Clement, S;
Gottardi, N;
Gowers, C;
Harbour, P;
Loarte, A;
Horton, L;
Lingertat, J;
Lowry, C G;
Saibene, G;
Stamp, M;
Stork, D;
[1]
Monk, R
[2]
- Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking
- Royal Holloway Coll., London (United Kingdom). Dept. of Physics
Citation Formats
Campbell, D J, Clement, S, Gottardi, N, Gowers, C, Harbour, P, Loarte, A, Horton, L, Lingertat, J, Lowry, C G, Saibene, G, Stamp, M, Stork, D, and Monk, R.
The density limit in JET diverted plasmas.
France: N. p.,
1994.
Web.
Campbell, D J, Clement, S, Gottardi, N, Gowers, C, Harbour, P, Loarte, A, Horton, L, Lingertat, J, Lowry, C G, Saibene, G, Stamp, M, Stork, D, & Monk, R.
The density limit in JET diverted plasmas.
France.
Campbell, D J, Clement, S, Gottardi, N, Gowers, C, Harbour, P, Loarte, A, Horton, L, Lingertat, J, Lowry, C G, Saibene, G, Stamp, M, Stork, D, and Monk, R.
1994.
"The density limit in JET diverted plasmas."
France.
@misc{etde_456161,
title = {The density limit in JET diverted plasmas}
author = {Campbell, D J, Clement, S, Gottardi, N, Gowers, C, Harbour, P, Loarte, A, Horton, L, Lingertat, J, Lowry, C G, Saibene, G, Stamp, M, Stork, D, and Monk, R}
abstractNote = {In JET limiter plasmas the density limit is associated with radiated power fractions of 100% and, in plasmas with carbon limiters, it is invariably disruptive. However, in discharges with solid beryllium limiters the limit is identified with the formation of a MARFE and disruptions are less frequent. In addition, the improved conditioning of the vessel arising from the use of beryllium has significantly improved the density limit scaling, so that the maximum density rises with the square root of the input power. In diverted plasmas several confinement regimes exist, making the characterization of the density limit more complex. While the density limit in L-mode plasmas is generally disruptive, the limit in ELMy and ELM-free H-modes generally prompts a return to the L-mode and a disruption is not inevitable. The density limit does rise with the increasing power, but the L-to-H transition complicates the analysis. Nevertheless, at low plasma currents (<2 MA), densities significantly above the Greenwald limit can be achieved, while at higher currents power handling limitations have constrained the range of density which can be achieved. (authors). 7 refs., 4 figs.}
place = {France}
year = {1994}
month = {Jul}
}
title = {The density limit in JET diverted plasmas}
author = {Campbell, D J, Clement, S, Gottardi, N, Gowers, C, Harbour, P, Loarte, A, Horton, L, Lingertat, J, Lowry, C G, Saibene, G, Stamp, M, Stork, D, and Monk, R}
abstractNote = {In JET limiter plasmas the density limit is associated with radiated power fractions of 100% and, in plasmas with carbon limiters, it is invariably disruptive. However, in discharges with solid beryllium limiters the limit is identified with the formation of a MARFE and disruptions are less frequent. In addition, the improved conditioning of the vessel arising from the use of beryllium has significantly improved the density limit scaling, so that the maximum density rises with the square root of the input power. In diverted plasmas several confinement regimes exist, making the characterization of the density limit more complex. While the density limit in L-mode plasmas is generally disruptive, the limit in ELMy and ELM-free H-modes generally prompts a return to the L-mode and a disruption is not inevitable. The density limit does rise with the increasing power, but the L-to-H transition complicates the analysis. Nevertheless, at low plasma currents (<2 MA), densities significantly above the Greenwald limit can be achieved, while at higher currents power handling limitations have constrained the range of density which can be achieved. (authors). 7 refs., 4 figs.}
place = {France}
year = {1994}
month = {Jul}
}