Multichannel far-infrared polarimeter system on <scp>TEXT</scp>-Upgrade

A far-infrared polarimeter diagnostic has been added to the UCLA multichord heterodyne interferometer system on TEXT-Upgrade. The polarimeter utilizes the phase technique of Rice [Rev. Sci. Instrum. 63, 5002 (1992)] in order to measure the Faraday rotation angle of the incident laser beam upon transmission through the plasma. From these data one derives information on the poloidal magnetic field, current density, and safety factor profiles. Due to the excellent port access and the polarimeter/interferometer scanning capability, the Faraday rotation profile can be measured across the entire plasma cross section.