X-ray ultraviolet absorption measurements of laser-driven Au∕CH∕Al multilayers

Abstract

X-ray ultraviolet absorption measurements of aluminum plasma at high temperature and high density are reported. A sample plasma was created by direct laser irradiation of a multilayered foil consisting of Au, CH, and Al. Observations were made using the method of self-backlighting spectroscopy. Simulations were performed with one-dimensional radiation-hydrodynamics code to compute the backlight profile as well as the time history of the density and temperature in the sample. By comparing the measured absorption spectra with detailed-term-accounting calculations at Te=120eV and ρ=0.1g∕cm3, it is found that the major spectral features predicted by calculations have been observed. Even better agreement between the experiment and the simulated absorption spectra was obtained by temporally averaging the radiation-hydrodynamics result over the backlight profile. This experiment shows that it is possible to measure high density and high temperature opacity by a laser-driven multilayer experiment.

Ion acceleration in the ‘dragging field’ of a light-pressure-driven piston

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“Light Sail” Acceleration Reexamined

“…The simple "Light Sail" model gives a good estimate of the energy per nucleon, but overstimates the conversion efficiency of laser energy into monoenergetic ions.Radiation Pressure Acceleration (RPA) of ultrathin solid targets by superintense laser pulses has been proposed as a promising way to accelerate large numbers of ions up to "relativistic" energies, i.e. in the GeV/nucleon range [1,2,3,4,5,6,7,8,9]. The simplest model of this acceleration regime is that of a "perfect" (i.e.…”

One-dimensional space resolving flat-field holographic grating soft x-ray framing camera spectrograph for laser plasma diagnostics

“…3 Taking the opacity property [4][5][6][7][8][9] of hot and dense matter as an example, the radiation opacity strongly depends on the status of the hot matter which changes quickly. Moreover, the hot dense matter emits x-rays itself by self-emission.…”