Anomalous transmission of high contrast relativistically intense short pulses through thin metal foils

The frequency doubled laser pulses from the T3 laser system at the Center for Ultrafast Optical Science of the University Michigan(1) (with energy up to 1 J, a pulse duration of 400 fs, the wavelength is 0.53 mu m and the maximum intensity is 2.7 x 10(19) W/cm(2)) has been used to measure the light transmitted through thin metal targets. The intensity contrast ratio of the laser pulse was better than 10(-9) which is low enough to suggest the interaction with solid density plasma without preplasma. We observed the transmittance of the laser pulse through the aluminum foil with thickness up to 4 mu m and found that this radiation is polarized and centered at 0.53 mu m. We found that for 0.8 mu m thick foils the transmission was anomalously high (similar to 10(-2)%) and can't be explained by the skin effect for relativistic pulse.