High-resolution spectroscopy of laser-produced plasmas in the photon energy range above 10 keV

X-rays from a laser-produced plasma were analysed using single-photon counting germanium detectors. Special attention was given to the extremely high photon flux, requiring either a long source-detector distance and narrow collimated measurement geometry in order to avoid severe pile-up of pulses in the spectrometer, or the use of a Compton scattering geometry. With the use of these techniques, individual characteristic K-lines were resolved for the first time. Efficiencies for the conversion of the laser light into X-rays were determined, being up to 10−4 for Bremsstrahlung, and up to 10−5 for the characteristic K-line emission. Electron temperatures of ∼100 keV were assessed.