Two-dimensional temperature spatial profiles and gradients in laser-heated plasmas relevant to MagLIF

We present measurements of two-dimensional temperature spatial profiles from magnetized and unmagnetized plasma experiments performed at Z relevant to the pre-heat stage of Magnetized Liner Inertial Fusion. The D gas fill was doped with a trace amount of Ar for spectroscopy purposes and time-integrated spatially resolved spectra and narrowband images were collected in both experiments. Individual analysis of the spatially resolved spectra recovers temperature profiles T$_{\mathrm{e}}$(z) that are resolved along the axial direction of laser propagation but spatially integrated along the instrument's line-of-sight. By including both the spectrum and image data in a multi-objective analysis, we have extracted two-dimensional electron temperature distributions T$_{\mathrm{e}}$(r,z). The results indicate that, by inhibiting radial thermal conduction, the magnetic field increased T$_{\mathrm{e}}$, the axial extent of the laser heating, and the magnitude of the radial temperature gradients. Comparisons with simulations reveal that the simulations over-predict the extent of the laser heating and under-predict the temperature. Temperature gradient scale lengths extracted from the measurements also permit an assessment of the importance of nonlocal heat transport.