VUV Radiation Bolometer for Beam-Heated Currentless Plasmas in Heliotron-E

Abstract
We have produced a filtered bolometer for monitoring radiation power in the vacuum ultraviolet region (150 Å–700 Å) to separate photon flux from change exchange neutral particles. The device consists of a thin aluminum filter and a metal film bolometer. It was determined that the VUV radiation carried 30–40% of the total radiated power to the wall under neutral beam injection heating (2 MW, H°→H+).