Ultrashort 1-kHz laser plasma hard x-ray source

We achieved a continuous, stable, ultrashort pulse hard x-ray point source by focusing 1.8-W, 1-kHz, 50-fs laser pulses onto a novel, 30-μm-diameter, high-velocity, liquid-metal gallium jet. This target geometry avoids most of the debris problems of solid targets and provides nearly 4π illumination. Photon fluxes of 5 X 10(8) photons/s are generated in a two-component spectrum consisting of a broad continuum from 4 to 14 keV and strong K_α and K_β emission lines at 9.25 and 10.26 keV. This source will find wide use in time-resolved x-ray diffraction studies and other applications. (C) 2002 Optical Society of America