title: Design and first plasma measurements of the ITER-ECE prototype radiometer.
abstract: On ITER, second harmonic optically thick electron cyclotron emission (ECE) in the range of 220-340 GHz will supply the electron temperature (Te). To investigate the requirements and capabilities prescribed for the ITER system, a prototype radiometer covering this frequency range has been developed by Virginia Diodes, Inc. The first plasma measurements with this instrument have been carried out on the DIII-D tokamak, with lab bench tests and measurements of third through fifth harmonic ECE from high Teplasmas. At DIII-D the instrument shares the transmission line of the Michelson interferometer and can simultaneously acquire data. Comparison of the ECE radiation temperature from the absolutely calibrated Michelson and the prototype receiver shows that the ITER radiometer provides accurate measurements of the millimeter radiation across the instrument band.
authors.affiliation: Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: M E
authors.initials: ME
authors.lastname: Austin
authors.affiliation: Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: M W
authors.initials: MW
authors.lastname: Brookman
authors.affiliation: Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: W L
authors.initials: WL
authors.lastname: Rowan
authors.affiliation: ITER-India/Institute for Plasma Research, Bhat, Gandhinagar 382428, India.
authors.forename: S
authors.initials: S
authors.lastname: Danani
authors.affiliation: Virginia Diodes, Inc., Charlottesville, Virginia 22902, USA.
authors.forename: E W
authors.initials: EW
authors.lastname: Bryerton
authors.affiliation: Virginia Diodes, Inc., Charlottesville, Virginia 22902, USA.
authors.forename: P
authors.initials: P
authors.lastname: Dougherty