Laser Proton Acceleration from Mass Limited Targets

We present recent studies on laser proton acceleration experiments using mass limited silicon targets. Small micro machined silicon foils with 2 µm thickness and 20x20 µm2 to 100x100µm2 size mounted on very tiny stalks were shot with ultra short laser pulses 30 fs of the new 150 TW DRACO Laser facility of the Research Centre Dresden-Rossendorf. The experiments were carried out using high contrast level 10-10. Proton spectra have been measured with magnetic spectrometers and radio chromic film stacks. The scaling of the maximum proton energy as function of the target size was investigated and strong influence of the stalk as well as the target edges was found.