A pulse-train laser driven XUV source for picosecond pump-probe experiments in the water window

We describe the development of a table top soft X-ray source based on a las er produced plasma. The plasma is produced by a Nd:YLF pulse-train laser wh ich delivers pulse trains of up to 400 pulses each of about 25 ps duration, Number and energy of the micropulses are fully computer controlled adjusta ble for an optimum interaction with a rotating solid target. Spectral, spat ial and temporal characteristics of the X-ray emission from Mylar and coppe r targets have been studied. A calibrated back-illuminated CCD camera toget her with a slit grating spectrograph were utilized for the measurement of t he absolute soft X-ray photon fluxes. The temporal measurements were perfor med using a streak camera while the plasma size was measured with a zone pl ate. An application of the system in a X-ray absorption experiment is shown , The advantages of the system in view of possible optical pump and soft X- ray probe experiments will be discussed. (C) 2001 Published by Elsevier Sci ence B.V.