Thermal pattern measurements during disruptions on TEXTOR-94

The thermal pattern onto the TEXTOR-94 toroidal limiter at the thermal quench for a set of four disruptions has been measured. A high temporal and spatial resolution camera, based on an infra-red 128 x 128 pixels focal plane array detector has been used to perform the measurements. Comparing the power profile for the same discharge as inferred from two images taken just before the disruption and at the thermal quench, it is possible to assess that: the radial exponential decay of the power flowing onto the limiter shows in both cases two different e-folding lengths, a short one (of the order of 2 mm or even less, in disruptive discharges) in the first few mm of the SOL depth and a larger one (1.5 cm) deeper in the SOL, An energy balance has been performed based on thermal images of both the limiter and the nearby wall during the thermal quench. The total energy lost is comparable to the plasma energy content. (C) 1999 Elsevier Science B.V. All rights reserved