Optimization of the lines of sight of the ITER x-ray crystal spectrometer diagnostic

The measurement performance of high-resolution x-ray crystal spectrometers foreseen for ITER has been investigated by numerical simulations. An Abel- inversion-like method is used to derive the ion temperature, and poloidal and toroidal rotation profiles. The performance with different viewing geometries and different ionization stages of impurities is investigated. Ion temperature profiles can be reconstructed within the ITER measurement requirements for most of the examined geometries. With conservative assumptions about detector sensitivity, low levels of injected impurities, and low rotation velocities, the velocity profiles can be reconstructed moderately well for the best geometries, with significant improvements if any of these parameters is increased. (C) 2004 American Institute of Physics