Polarization-Sensitive Measurements Of Magnetic Fields In Magnetized Plasmas Using Zeeman Broadening Diagnostics

The Zeeman effect has been used to measure the magnetic field in high energy density plasmas. The measurements are difficult in this regime because the line broadening due to the high plasma density and temperature surpasses the Zeeman splitting. Using an idea proposed by Tessarin \textit{et al}. (2011), we have measured the field in magnetized laser plasmas and in the current-driven exploding wire plasmas. Time-gated spectra with one-dimensional space-resolution were obtained at the Nevada Terawatt Facility for laser plasmas created by 20 J, 1 ns Leopard laser pulses, and expanding in the azimuthal magnetic field produced by the 0.6 MA Zebra pulsed power generator, and for wire array plasmas driven by the 1 MA configuration of the Zebra generator. We explore the response of the Al III 4s $^{\mathrm{2}}$S$_{\mathrm{1/2\thinspace }}$-- 4p $^{\mathrm{2}}$P$_{\mathrm{1/2,3/2}}$ doublet components to the external magnetic field spatially along the plasma in two orthogonal polarizations. In these measurements the Zeeman splitting was not resolved, but the magnetic field strength was measured from the difference between the widths of the line profiles.