Soft X-Ray Diagnostics on the Compact Toroidal Hybrid Experiment

Soft X-Ray (SXR) Diagnostics are used on the Compact Toroidal Hybrid (CTH) torsatron experiment (R = 0.75 m, a $\sim $ 0.2 m, B $\le $ 0.7 T, n$_{e}$ $\le $ 10$^{19}$ m$^{-3}$, T$_{e} \quad \le $ 250 eV) for tomographic reconstruction of the emissivity profile, electron temperature measurement, and as input to a 3D reconstruction code. SXR tomography is performed with three cameras with up to 60 chords viewing a poloidal cross-section. Each camera consists of a 20-channel AXUV-20EL photo-diode array filtered with 500nm Al foil. Electron temperatures are being measured with an Amptek X123-SDD spectrometer. The spectrometer views the Bremsstrahlung emission along a single chord through the plasma in the energy range from 1-10 keV. Signals from the 60 channel tomographic camera system and signals from similar cameras located at other toroidal locations are being incorporated into the V3FIT reconstruction code[1]. [1]. J. D Hanson et. al., Nucl. Fusion \textbf{49}, 075031 (2009)