Measurements with magnetic field in the National Spherical Torus Experiment using the motional Stark effect with laser induced fluorescence diagnostic

Foley, E. L.; Levinton, F. M.
April 2013
Review of Scientific Instruments;Apr2013, Vol. 84 Issue 4, p043110
Academic Journal
The motional Stark effect with laser-induced fluorescence diagnostic (MSE-LIF) has been installed and tested on the National Spherical Torus Experiment (NSTX) at the Princeton Plasma Physics Lab. The MSE-LIF diagnostic will be capable of measuring radially resolved profiles of magnetic field magnitude or pitch angle in NSTX plasmas. The system includes a diagnostic neutral hydrogen beam and a laser which excites the n = 2 to n = 3 transition. A viewing system has been implemented which will support up to 38 channels from the plasma edge to past the magnetic axis. First measurements of MSE-LIF signals in the presence of small applied magnetic fields in neutral gas are reported.


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