A multichannel far infrared (FIR) polarimeter has been installed on the reversed field experiment (RFX) to measure the poloidal magnetic field profile, BΘ. The polarimeter uses a FIR laser (λ = 118.8 μm) whose beam is transmitted to the machine via a 31 m long, nitrogen filled beam line. Faraday rotation measurements are reported for five of six parallel chords crossing the 1 m diameter RFX plasma on a poloidal cross section. The density profile is known from a CO2interferometer. Low noise deuterated L-alaine doped triglycene sulphate (DLATGS) detectors are used. An accuracy of about 0.2° is obtained in the measured Faraday rotation angle, which is sufficient to estimate the characteristics of the BΘprofile. Removal of the noise induced by mechanical vibrations allowed acceptable measurements of Faraday rotation angles. © 2001 American Institute of Physics.
All Science Journal Classification (ASJC) codes
O'Gorman, M., Zilli, E., Giudicotti, L., Prunty, S., Milani, F., Murari, A., & Boboc, A. (2001). The multichord far infrared polarimeter of the RFX experiment. Review of Scientific Instruments, 72(1 II), 1063 - 1066. https://doi.org/10.1063/1.1319365