Density Limit Disruption Studies in the Compact Toroidal Hybrid Experiment using Machine Learning Based Bolometer Inversions

Recent bolometer data from density limit disruption studies in the Compact Toroidal Hybrid (CTH) at Auburn University show spatial and temporal correlations with poloidal magnetic field fluctuations. Using line-of-sight approximations, the source of the bolometer fluctuations appears to lie on the reconstructed  flux surface. Using a De-Convolutional Neural Network to inverted the bolometer data, the inverted bolometer fluctuations rotate spatially with the measured magnetic field fluctuations which have the form of a  MHD mode. This result points to the origination of the bolometer fluctuations to be on the O-points of the 2/1 mode. The intensity of the bolometer and poloidal magnetic field fluctuations grow synchronously and rapidly just before the density limit disruption.

* Work supported by USDOE grant DE-FG02-00ER54610