Irradiation of parylene disks with a 1.06 μm laser

Abstract

Parylene (C8H8) disks have been irradiated with Nd:YAG-glass laser pulses focused to flux levels in the 1015 to 1017 W/cm2 range. The flux level was varied by changing the pulse length (50–150 psec), the laser energy (5–15 J), and the axial position of the target with respect to the f/1.1 focusing lens. An extensive array of diagnostics was used to measure the temporal and energy distribution of the focused laser light at the target, the temporal and angular distribution of the scattered laser light, the x-ray spatial and spectral emission characteristics, and the emitted ion and electron energy distributions. The experimental results, together with two-dimensional numerical simulations imply absorption via collective processes, laser generation of suprathermal electrons, and transport inhibition consistent with the presence of mega-Gauss level thermoelectric magnetic fields.