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Metallic nanoparticles have been obtained by 10 10 W/cm 2 Nd:YAg laser ablation in liquid at different irradiation conditions. The nanoparticles were based on Au, Ag, Ti and Cu with means size ranging between 10 nm and 100 nm at different concentrations. Nanoparticles were analyzed with optical absorption spectroscopy in the wavelength range 300-1000 nm. The resulting solutions have been deposited or embedded on different thin polymeric substrates (mylar, nuclepore, polyethylene). The laser irradiation of the prepared thin targets produces a backward plasma emission characterized by ion acceleration. Plasma was monitored in vacuum through ion collectors employed in time of flight configuration. The measurements reveal a significant ion acceleration enhancement of proton and carbon ions in the case of metal nanoparticles with respect to the case without, due to the increment of the laser energy deposition in the prepared targets for Surface Plasmon Resonant (SPR) absorption effect.

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Non-equilibrium plasma generated by nanosecond pulsed laser are characterized by solid state 4H-SiC interdigit Schottky diodes and by a large area ion collector detector, both connected in time-of-flight configuration. Plasma generated by irradiation of different metallic targets through a pulsed laser with a 1010 W/cm2 intensity and a 200 mJ energy, where monitored. In this paper we demonstrate that the interdigit 4H-SiC diode is able to detect ultraviolet radiation and soft X-rays, with energy of the order of 20 eV with very short rise time, of a few nanoseconds, and high efficiency, comparable with the performance of traditional large area ion collectors. Thanks to their millimetric size, solid state 4H-SiC detectors are good candidates for the fabrication of array systems for the spatial distribution measurement of plasma radiation. Moreover, owing to the their high efficiency and the interdigit geometry of front electrode, 4H-SiC diodes here proposed are suitable also for low energy ions detection.

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