Development of a spectroscopic technique for simultaneous magnetic field, electron density, and temperature measurements in ICF-relevant plasmas

Spectroscopic techniques in the visible range are often used inplasma experiments tomeasure B-field inducedZeeman splitting,electron densities via Stark broadening, andtemperatures fromDoppler broadening. However, whenelectron densities andtemperatures are sufficiently high, the broadening of the Stark andDoppler components can dominate theemission spectra and obscure theZeeman component. In this research, we are developing a time-resolved multi-axial technique formeasuring theZeeman, Stark, andDoppler broadened line emission of dense magnetized plasmas for Z-pinch and DensePlasma Focus (DPF) accelerators. The line emission is used to calculate theelectron densities,temperatures, and B-fields. In parallel, we are developing a line-shape modeling code that incorporates the broadening effects due to Stark,Doppler, andZeeman effects for dense magnetized plasma. This manuscript presents the details of the experimental setup and line shape code, along with the results obtained from anAliii doublet at the University of Nevada, Reno at Nevada Terawatt Facility. Future tests are planned to further evaluate the technique and modeling on other material wire array, gas puff, and DPF platforms.

Source: Review of Scientific Instruments - October 18, 2016 Category: Physics Authors: E. C. Dutra, J. A. Koch, R. Presura, W. A. Angermeier, T. Darling, S. Haque, R. C. Mancini and A. M. Covington Source Type: research