The x-ray emission, ablation pressure, and preheating for foils irradiated at 0.26 μm wavelength

The x-ray emission, ablation pressure, and preheating for foils irradiated with a 0.26 μm laser at intensities ∼1015 W cm−2 are studied. The foils are Al with various thicknesses, coated or uncoated with CH or Au. The x-ray emission and conversion efficiency are obtained with a multichannel x-ray diode spectrometer, the ablation pressures are deduced from shock transit times, and the rear temperatures are inferred from x-ray pyrometry. For thin foils (≪12 μm), the rear temperatures can be predicted reasonably well with the use of the front x-ray spectra. For thick foils shock preheating is dominant.