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The detailed knowledge of fast electron energy transport following interaction with high-intensity, ultra-short laser pulses is a key area for secondary source generation for ELI. We demonstrate polarization spectroscopy at laser intensities up to 1021 Wcm-2. This is significant as it suggests that in situ emission spectroscopy may be used as an effective probe of fast electron velocity distributions in regimes relevant to electron transport in solid targets. Ly-α doublet emission of nickel (Z = 28) and sulphur (Z = 16) is observed to measure the degree of polarization from the Ly-α1 emission. Ly-α2 emission is unpolarized, and as such acts as a calibration source between spectrometers. The measured ratio of the X-ray σ-and π-polarization allows the possibility to infer the velocity distribution function of the fast electron beam. © 2010 American Institute of Physics.

Plasmas generated by irradiating targets with ∼20 kJ of laser energy are routinely created in inertial confinement fusion research. X-ray spectroscopy provides one of the few methods for diagnosing the electron temperature and electron density. For example, electron densities approaching 1024 cm−3 have been diagnosed by spectral linewidths. However, the accuracy of the spectroscopic diagnostics depends the population kinetics, the radiative transfer, and the line shape calculations. Analysis for the complex line transitions has recently been improved and accelerated by the use of a database where detailed calculations can be accessed rapidly and interactively. Examples of data from Xe and Ar doped targets demonstrate the current analytic methods. First we will illustrate complications that arise from the presence of a multitude of underlying spectral lines. Then, we will consider the Ar He-like 1s2(1S0)−1s3p(1P0) transition where ion dynamic effects may affect the profile. Here, the plasma conditions are ...

An experiment to create highly uniform shocks in crystalline solids suitable for studying the thickness of shock fronts by in situ x-ray diffraction is described. A laser is used to create a soft x-ray radiation source. This radiation source heats a thin layer of the silicon crystal; the ablation of this layer produces a uniform near-one-megabar shock. We discuss how x-ray diffraction can be used to measure the shock front thickness from a uniformly shock compressed solid. The x-ray diffraction technique is described through previously measured experimental data and by comparison to simulated diffraction records.