Characterization of plasma temperatures and heat fluxes during HIDRA operation*

HIDRA is a medium-sized stellarator/tokamak hybrid operated at the University of Illinois at Urbana-Champaign. With a primary research objective of exposing novel plasma-facing component (PFC) technologies to steady-state plasma conditions, this device is typically used in its configuration as an l = 2, m = 5 stellarator. In order to assess the performance of PFCs in HIDRA, it is necessary to characterize the plasma temperature, as well as heat fluxes to limiting surfaces, during normal operation. These measurements are made by employing a set of optical spectrometers and a pair of infrared cameras, which have all been equipped with mountings that allow placement at multiple locations around the machine. Measurements will be presented here of the operating temperatures and heat fluxes achieved in HIDRA with up to 26 kW of microwave heating power.