TY - JOUR
T1 - MHD activity triggered by monster sawtooth crashes on Tore Supra
AU - Maget, P.
AU - Artaud, J.-F.
AU - Eriksson, L.-G.
AU - Huysmans, G.T.A.
AU - Lazaros, A.
AU - Moreau, P.
AU - Ottaviani, M.
AU - Segui, J.-L.
AU - Zwingmann, W.
PY - 2005/2/1
Y1 - 2005/2/1
N2 - The crash of monster sawteeth in Tore Supra ion cyclotron resonance
heated plasmas is observed to trigger long-lived magneto hydrodynamic
(MHD) activity, dominated by a (m = 3, n = 2) magnetic perturbation at
the edge. This phenomenon is reminiscent of the triggering of
neoclassical tearing modes, although in Tore Supra the MHD activity
decays and eventually vanishes. It can be explained by the linear
destabilization of the (3, 2) mode as the current sheet developed in the
non-linear stage of the internal kink relaxation gets closer to q = 3/2.
However, the lifetime of the (3, 2) island is longer than the period of
linear instability. We find that the neoclassical drive is essential for
explaining the observed lifetime and width of the island, although the
overall dynamics is controlled by the relaxation of the current profile
on a resistive time scale.
AB - The crash of monster sawteeth in Tore Supra ion cyclotron resonance
heated plasmas is observed to trigger long-lived magneto hydrodynamic
(MHD) activity, dominated by a (m = 3, n = 2) magnetic perturbation at
the edge. This phenomenon is reminiscent of the triggering of
neoclassical tearing modes, although in Tore Supra the MHD activity
decays and eventually vanishes. It can be explained by the linear
destabilization of the (3, 2) mode as the current sheet developed in the
non-linear stage of the internal kink relaxation gets closer to q = 3/2.
However, the lifetime of the (3, 2) island is longer than the period of
linear instability. We find that the neoclassical drive is essential for
explaining the observed lifetime and width of the island, although the
overall dynamics is controlled by the relaxation of the current profile
on a resistive time scale.
U2 - 10.1088/0741-3335/47/2/010
DO - 10.1088/0741-3335/47/2/010
M3 - Article
SN - 0741-3335
VL - 47
SP - 357
EP - 377
JO - Plasma Physics and Controlled Fusion
JF - Plasma Physics and Controlled Fusion
IS - 2
ER -