RESUMO
A picosecond, time-resolved, x-ray spectroscopy platform was developed to study the thermal line emission from rapidly heated solid targets containing buried aluminum or iron layers. The targets were driven by high-contrast 1ω or 2ω laser pulses at focused intensities up to 1 × 1019 W/cm2. The experimental platform combines time-integrating and time-resolved x-ray spectrometers. Picosecond time resolution was achieved with a pair of ultrafast x-ray streak cameras coupled to high-throughput Hall spectrometers. Time-integrated spectra were collected on each shot to correct the streaked data for variations in x-ray photocathode spectral sensitivity. The time-integrated spectrometer uses three elliptical crystals to disperse x rays with energies between 800 and 2100 eV with moderate (E/ΔE â¼ 450) resolving power. The streaked spectrometers accept four interchangeable conical crystals with higher resolving power (E/ΔE â¼ 650) to measure the brightest thermal lines in the 1300 to 1700 eV spectral range.