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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.

Helium‐like aluminium (Z=13) plasmas created using long (nanosecond) and short (picosecond) duration laser pulses at intensities between 5 × 1013 and 5 × 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 inte...

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.

Laboratory astro-plasma physics experiments are being designed to advance both our astrophysics and plasma physics knowledge. With current laser technology, target design and diagnostics, it is now possible to reproduce and measure the conditions of temperature and pressure usually met in extreme stellar environments. Coupled with scaled plasma physics it is possible to simulate certain aspects of astrophysical phenomena in the laser laboratory. The focus is on experiments designed to address key aspects of the plasma physics occurring in supernova remnants. In this approach ideal magneto-hydrodynamics is applied to the supernova remnant and then scaled. Matching dimensionless parameters in a laboratory experiment enables the simulation of complex astro-plasma systems offering the advantage of repeated, detailed measurements and the flexibility to alter the input conditions. Work at York has centered on developing a collisionless plasma experiment. The experiment involves a magnetic field, and two laser-exploded plasmas to make possible a laboratory study of the interaction between a supernova remnant and the interstellar medium. These experiments and the analysis are discussed.