Bolometric measurements in JT-60

Radiation losses from the main plasma of the JAERI Tokamak-60 (JT-60) were measured by a 15-channel bolometer array and those from divertor chambers in the ion and electron drift sides were each measured by two bolometers. The bolometric detector consisting of three layers (5-μm-thick gold absorber, 7-μm-thick polyimide foil, and 0.1-μm-thick gold resistor grid) was developed for this measurement. In typical diverted discharges with NB heating, the ratios of power radiated from the main and divertor chambers to the absorbed power were approximately 10% and 20%, respectively. Intense poloidal asymmetries of radiated power localized near the X point outside the torus were observed in diverted discharges. The profiles of the radiated power were reconstructed by an Abel inversion with an asymmetric term. On the other hand, a poloidally asymmetric radiation band localized near the inner wall, ''marfe,'' was observed for dense plasmas in limiter discharges with neutral beam heating