[en] We discuss the processing of x-ray absorption spectra from photoionized plasma experiments at Z. The data was recorded with an imaging spectrometer equipped with two elliptically bent potassium acid phthalate (KAP) crystals. Both time-integrated and time-resolved data were recorded. In both cases, the goal is to obtain the transmission spectra for quantitative analysis of plasma conditions.

[en] Laboratory experiment is an attractive method of exploring the plasma physics that may occur in solar and astrophysical shocks. An experiment enables repeated and detailed measurements of a plasma as the input conditions are adjusted. To form a scaled experiment of an astrophysical shock a plasma physics model of the shock is required, and the important dimensionless parameters identified and reproduced in the laboratory. A laboratory simulation of a young supernova remnant is described. The experiment uses the interaction of two millimetre-sized counter-streaming laser-produced plasmas placed in a strong transverse magnetic field to achieve this scaling. The collision-free dynamics of the two plasmas and their interaction are studied with and without the magnetic field through spatially and temporally resolved optical measurements. Laboratory astroplasma physics experiments using high-energy, high-power laser technology enables us to reproduce in the laboratory the conditions of temperature and pressure that are met in extreme stellar environments

[en] The Z facility at the Sandia National Laboratories is the most energetic terrestrial source of X-rays and provides an opportunity to produce photoionized plasmas in a relatively well characterised radiation environment. We use detailed atomic-kinetic and spectral simulations to analyze the absorption spectra of a photoionized neon plasma driven by the x-ray flux from a z-pinch. The broadband x-ray flux both photoionizes and backlights the plasma. In particular, we focus on extracting the charge state distribution of the plasma and the characteristics of the radiation field driving the plasma in order to estimate the ionisation parameter

[en] X-ray Thomson scattering (XRTS) is a powerful technique for measuring state variables in dense plasmas. In this paper, we report on the development of a one-dimensional imaging spectrometer for use in characterizing spatially nonuniform, dense plasmas using XRTS. Diffraction of scattered x-rays from a toroidally curved crystal images along a one-dimensional spatial profile while simultaneously spectrally resolving along the other. An imaging spectrometer was fielded at the Trident laser at Los Alamos National Laboratory, yielding a FWHM spatial resolution of < 25 μm, spectral resolution of 4 eV, spectral range of 350 eV, and spatial range of > 3 mm. A geometrical analysis is performed yielding a simple analytical expression for the throughput of the imaging spectrometer scheme. The SHADOW code is used to perform a ray tracing analysis on the spectrometer fielded at the Trident Laser Facility understand the alignment tolerances on the spatial and spectral resolutions. The analytical expression for the throughput was found to agree well with the results from the ray tracing.

[en] Highly ionized aluminium plasmas created using long (nanosecond) and short (picosecond) duration laser pulses are studied using a combination of high resolution X-ray spectroscopy and computational modeling tools. The experiments are designed to be simple and the emission spectra well characterized so that detailed observation of strong, single frequency electric fields effects can be observed and studied. Strong oscillating electric fields can modify the emission spectra of ions by altering spectral line shapes, through ionization processes, and the appearance of field-induced satellite lines. However, field-induced effects are expected to be weak, thus high dispersion, high luminosity spatially resolving spectrometers are employed. Initial results are discussed and an example of a possible field induced modification of a spectral line shape is presented

[en] Helium-like aluminium (Z=13) plasmas created using long (nanosecond) and short (picosecond) duration laser pulses at intensities between 5 x 1013 and 5 x 1016 W/cm2 were studied using a combination of optical and X-ray spectroscopy methods and computational modeling tools. The experiments were designed to ensure that the K-shell emission spectra from the aluminium plasmas was measured in detail and that the spectra could be reproduced through a combination of hydrodynamic, atomic kinetic, and radiation transport models. Detailed spectral line shapes, with high spectral and spatial resolution, were recorded in an attempt to positively observed single frequency electric fields effects due to the application of a strong laser field, and due to strong laser-driven plasma waves. Spectral line shape modification due to laser-driven plasma waves was observed, yet there is no evidence for direct laser field effects. Experimental procedures and the computational work are outlined, the observation of modulated intensity profiles on the He-β transition and the interpretation based on intra-Stark spectroscopy discussed