X-ray spectral measurement of high-temperature plasma parameters in porous targets irradiated with high-power laser pulses

The X-ray spectra of multiply charged ions were recorded from planar agar (C12H18O9)n based targets with an average density of 2 mg cm-3 irradiated by high-power laser pulses (λ=1.054 μm, τ=2.5 ns, I ≈ 5 ×1013 W cm-2). The spectra were recorded with a high spectral and spatial resolution employing spherically bent (focusing) crystals of mica and quartz. An analysis of the experimental data obtained by the irradiation of Al2O3-doped agar samples allowed us to determine the main parameters of the plasma produced inside the targets. The ion temperature of plasma in low-density porous targets was estimated for the first time to be 1.5 — 2 times higher than the electron temperature.