Experimental demonstration of an electromagnetic pulse mitigation concept for a laser driven proton source.

The targets that are used to produce high-energy protons with ultra-high intensity lasers generate a strong electromagnetic pulse (EMP). To mitigate that undesired side effect, we developed and tested a concept called the "birdhouse." It consists in confining the EMP field in a finite volume and in dissipating the trapped electromagnetic energy with an electric resistor.

Proton emission from thin hydrogenated targets irradiated by laser pulses at 10(16) W∕cm2.

The iodine laser at PALS Laboratory in Prague, operating at 1315 nm fundamental harmonics and at 300 ps FWHM pulse length, is employed to irradiate thin hydrogenated targets placed in vacuum at intensities on the order of 10(16) W∕cm(2). The laser-generated plasma is investigated in terms of proton and ion emission in the forward and backward directions. The time-of-flight technique, using ion collectors and semiconductor detectors, is used to measure the ion currents and the corresponding velocities and energies.

Generation of solid-density ultraintense ion beams by a picosecond laser pulse of circular polarization.

This contribution reports particle-in-cell numerical studies of deuteron beam acceleration by a picosecond laser pulse of circular polarization. The effect of laser wavelength λ and the I(L)λ(2) product (I(L) is laser intensity) on the ion beam parameters is investigated. It is shown that at the I(L)λ(2) product fixed, the beam parameters (, I(i), F(i)) as well as the laser-ions energy conversion efficiency quickly increase with a decrease in the laser wavelength and the best results are achieved for a KrF laser (λ = 0.

Fast proton generation from ultrashort laser pulse interaction with double-layer foil targets.

The results of studies of fast-proton generation from foil targets irradiated by 1-ps laser pulse at 10(17) W/cm (2) are presented. It is shown that a considerable increase in proton energy and current is possible when a double-layer foil target containing a high- Z layer and a low- Z hydrogen-rich layer is used instead of a single-layer target. Proton energies and current increase with the Z of the high- Z layer and depend essentially on the target and the layer thicknesses.