| Popis: |
We are performing laser matter interaction studies with the P102 laser in picosecond and sub‐picosecond range at 1018 W/cm2. We describe an X‐ray RbAP conical crystal spectrometer (spectral resolution 5 mA in 6.86 A–8.5 A spectral range) developed to increase its sensitivity by a factor 200 compared with the one of a plane crystal used in the same conditions. By using this spectrometer and the C850X bilamellar X‐ray streak camera (2 ps, 20 lp/mm), we have recorded tiime resolved X‐ray spectra emitted from an aluminum plasma. We observed Hα, Heα, Li‐like, Be‐like, and Kα lines versus time. Intensity and duration of the line emission are very dependent on the contrast ratio of the laser pulse and are interpreted as a function of the scale length of the pre plasma created before the main pulse arrives onto the target. |
