EXPLANATION FOR MARFE FORMATION AND SUBSEQUENT EVOLUTION INTO A DETACHED SYMMETRICAL PLASMA EDGE - COMMENT

W. M. Stacey presents stability criteria for the thermal instability b ased on a linear one-dimensional (1D) slab model including the effects of ionization recombination [Phys. Plasmas 3, 2673 (1996)], large rad ial gradients and rotation [Phys. Plasmas 3, 3032 (1996)] and external edge heating [Phys. Plasmas 4, 134 (1997)]. The second paper is incor rectly presented as a two-dimensional (2D) analysis. The hypothesis fo r the poloidal asymmetry of the multifaceted asymmetric radiation from the edge (MARFE) is based on a misinterpretation of the linear result s and contradicted by our own linear analyses in a 1D cylindrical [Phy s. Plasmas 1, 2623 (1994)] and a 2D tokamak model [Plasma Phys. Contro lled Fusion 39, 423 (1997)]. The explanation for the evolution into a detached plasma and for MARFE suppression by external edge heating are interesting hypotheses, supported by experimental observations. Howev er, a 1D Linear analysis does not offer the basis to support these hyp otheses theoretically. (C) 1997 American Institute of Physics.