A comparison of fluctuation spectra from microwave scattering and beam emission spectroscopy on TFTR (abstract)

A comparison of fluctuation spectra from both microwave scattering and beam emission spectroscopy (BES) on TFTR has been done at similar values of k and in a plasma in which the toroidal rotation and density profile have been well characterized. The two systems measure somewhat different values of k (k<1.5 cm-1 for BES and k>2.5 cm-1 for microwave scattering) and average over somewhat different regions of space (2--3 cm for BES and 30--40 cm for microwave scattering). As a result, the observed spectra can be different because of intrinsic differences in |left-angle δne(k)right-angle |2 and because the spectra are affected differently by plasma rotation. Nevertheless, when beam induced toroidal plasma rotation is known or is minimized and the two systems are looking at similar spatial locations, the results from the two systems are similar and respond in the expected way to changes in toroidal rotation. A detailed discussion of several model cases will be presented