(OV/4-1) Overview of Recent Alcator C-Mod Research
E.S. Marmar1),
B. Bai1),
R.L. Boivin4),
P.T. Bonoli1),
C. Boswell1),
R. Bravenec3),
B. Carreras5),
D. Ernst1),
C. Fiore1),
S. Gangadhara1),
K. Gentle3),
J. Goetz6),
R. Granetz1),
M. Greenwald1),
K. Hallatschek7),
J. Hastie15),
J. Hosea2),
A. Hubbard1),
J.W. Hughes1),
I. Hutchinson1),
Y. In12),
J. Irby1),
T. Jennings1),
D. Kopon16),
G. Kramer2),
B. LaBombard1),
W.D. Lee1),
Y. Lin1),
B. Lipschultz1),
J. Liptac1),
A. Lynn3),
K. Marr1),
R. Maqueda8),
E. Melby9),
D. Mikkelsen2),
D. Mossessian1),
R. Nazikian2),
W.M. Nevins13),
R. Parker1),
T.S. Pedersen10),
C.K. Phillips2),
P. Phillips3),
C.S. Pitcher11),
M. Porkolab1),
J. Ramos1),
M. Redi2),
J. Rice1),
B.N. Rogers14),
W.L. Rowan3),
M. Sampsell3),
G. Schilling2),
J. Snipes1),
P. Snyder4),
D. Stotler2),
G. Taylor2),
J.L. Terry1),
H. Wilson15),
J.R. Wilson2),
S.M. Wolfe1),
S. Wukitch1),
X.Q. Xu13),
B. Youngblood1),
H. Yuh1),
K. Zhurovich1),
S. Zweben2)
1) Massachusetts Institute of Technology, Cambridge, MA, USA
2) Princeton Plasma Physics Laboratory, Princeton, NJ, USA
3) University Texas, Austin, TX, USA
4) General Atomics, San Diego, CA, USA
5) Oak Ridge National Laboratory, Oak Ridge, TN, USA
6) University of Wisconsin, Madison, WI, USA
7) Max Planck Insitute for Plasma Physics, Garching, Germany
8) Los Alamos National Laboratory, Los Alamos, NM, USA
9) CRPP, Lausanne, Switzerland
10) Columbia University, New York, NY, USA
11) Institute for Aerospace Studies, University of Toronto, Toronto, Ontario, Canada
12) University of Idaho, Moscow, ID, USA
13) Lawrence Livermore National Laboratory, Livermore, CA, USA
14) Dartmouth University, Hanover, NH, USA
15) EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxon, UK
16) Cornell University, Ithaca, NY, USA
Abstract. Experiments have been carried out to investigate the triggering
and control of ITBs, using multiple frequency ICRF tools. It is found that
the ITBs can be reliably triggered using off-axis ICRF minority heating; the
addition of on-axis heating at a second frequency can be used for control of
the particle transport, leading to quasi-steady operation. Cross-field
particle transport in the SOL been shown to be very rapid in Alcator C-Mod
usually dominating over the parallel transport into the divertor with very
important implications for our understanding of particle recycling and ash
removal. Detailed explorations of the quasi-coherent mode (QCM) that appears
to be responsible for particle transport across the EDA H-mode barrier have
revealed that the QCM has a magnetic component, and comparisons with MHD
stability calculations are consistent with the hypothesis that it is due to
a resistive ballooning instability. In preparation for long-pulse discharges
which will be sustained non-inductively we have produced discharges up to 3
seconds in length confirming that all systems can be operated for at least
5-second shots, which corresponds to about 5 current relaxation times at 5
keV.
IAEA 2003