Reflectometry for Density Fluctuation and Profile Measurements in TST-2

First Density Profile Measurements Using FMCW Reflectometry on JET

Plasma curvature effects on microwave reflectometry fluctuation measurements

Plasma poloidal curvature can significantly extend microwave reflectometry responses to high k⊥ poloidal fluctuations. Reflectometry responses can be several orders of magnitude larger at high k⊥ than that predicted by analysis based on two dimensional (2-D) slab geometry. As a result, the responses may approach the 1-D geometrical optics limit. This super resolution leads to a major modificati...

Density profile measurements with X-mode lower cut-off reflectometry in ASDEX Upgrade.

Despite the fact that density profile measurements using X-mode lower cut-off reflectometry are foreseen to be used on ITER, little or no experience is available within the reflectometry community and to our knowledge no results on this subject have been published so far. In ASDEX Upgrade the multichannel broadband reflectometer is equipped with b...

Ongoing work towards real-time reflectometry density profile measurements on ASDEX Upgrade

Previous studies performed in ASDEX Upgrade ELMy H-mode regimes (Santos et al. [2003]), ITER reference scenario, have shown that O-mode FM-CW reflectometry should meet the accuracy required on ITER for using reflectometry for position control purposes. This application, however, requires the development of robust unsupervised methods to evaluate the density profiles in real time. To allow a sta...

Comparison of Edge Fluctuation Measurements from PCI, BES, Langmuir Probes and Reflectometry on DIII–D

Phase contrast imaging (PCI), beam emission spectroscopy (BES), reflectometry, and Langmuir probes provide different but complementary measurements of the density fluctuations in the edge of the DIII–D tokamak plasma. In particular, the PCI is sensitive to modes with kθ kr, while the BES and probe response depends less on the angle of ~k⊥. On plasma discharges in which these diagnostics collect...