Progress on MSE-LIF diagnostic for NSTX-U

The motional Stark effect with laser-induced fluorescence diagnostic (MSE-LIF) was installed on NSTX during the 2011 run year. The MSE-LIF will enable radially resolved measurements of the magnetic field pitch angle and magnitude, both of which can be used to constrain plasma equilibrium reconstructions. A diagnostic neutral beam with low axial energy spread, low divergence, and high reliability has been developed. It operates routinely at 35 kV and 40~mA. A laser has been developed with high power (~10 W) and optimal linewidth matched to the energy spread of the neutral beam (~6\,GHz). The laser wavelength is near 651 nm for a match to the Doppler-shifted Balmer-alpha transition in the beam neutrals. The unique high-power, moderate linewidth laser system utilizes a 19 emitter diode laser bar and feedback from a volume Bragg grating for line width narrowing. Progress on the development of the MSE-LIF diagnostic toward initial operation during NSTX-U plasma operations will be presented, and highlights from the first run year will be discussed.