Bolometric Measurement of Reversed Field Pinch Plasma in TPE-1R (M)

Abstract

Measurments of radiation loss from RFP plasma in TPE-1R(M) have been made using a multi-layer thin film bolometer. In normal operating conditions of TPE-1R(M), the radiation loss has less effect on the global power balance since only 10–15% of joule input power is lost by the radiation. However, it increases to 35% or more in the high plasma current region. The content of iron impurity is estimated at 1–3% of the electron density from the measured radiation power in typical discharges. The volt-second consumption during the start-up phase has also been measured. The resistive volt-second loss for setting-up the RFP configuration is evaluated to be about 50% of the applied volt-second into the linear, which corresponds to ∼1/3 of the total volt-second, and is proportional to the plasma current to be established.