Heating of High z Plasma by Laser

The properties of plasmas produced by high power laser were investigated. The laser beam was irradiated on the various targets of beryllium Be, carbon C and polyethylene (CH 2 ) n of high z number. The influence of the charge number z to the heating of the plasma was discussed. The electron temperatures of plasmas from different targets were estimated by the measurement of soft X-ray. The time variations of the reflected laser light from plasma were also investigated. From the time of flight measurements with a Faraday cage and an electrostatic energy analyser, the different charged ions could be separated and ion temperatures and drift velocities were obtained from their velocity profiles. No influence of laser pulse duration to the temperature was observed in the cases of durations 2 n s , 4 n s and 10 n s . The experimental results for fast rising laser pulse were discussed and compared with those for slow rising one.