Tritium to deuterium ratio measurement by collective Thomson scattering

A technique is proposed for the determination of the tritium to deuterium density ratio in ITER using collective Thomson scattering at a wavelength of 10 mu m. The measurement is made by viewing the component of scattered laser power nearly perpendicular to the magnetic field giving rise to ion cyclotron modulation of the scattered spectrum. The tritium/deuterium ratio may be inferred by a deconvolution of the scattered laser power. Due to the narrow bandwidth of the scattered signal and the spatially varying magnetic field, a narrowband heterodyne imaging array receiver will be required to observe the scattered spectrum. (C) 1997 American Institute of Physics.