Soft X-ray computer tomography of sawtooth collapse associated with m=2 and m=3 modes with five detector arrays on the WT-3 Tokamak

Abstract

Another kind of sawtooth collapse is observed in a lower hybrid current drive plasma on the WT-3 tokamak. The internal structure of the plasma is investigated using computer tomography with five soft X-ray detector arrays after the application of the singular value decomposition to the soft X-ray detector signals. It is found that the precursor and postcursor oscillations of this collapse are the m=3 mode and the m=2 mode, respectively.