Guided acceleration of nanoparticles by laser irradiated parallel gold nanorods

Laser irradiated parallel gold nanorods with interspersed deuterium nanoparticles are shown to offer guided acceleration of nanoparticles. The laser pulse of intensity exceeding 1018W/cm2 at 1 μm wavelength and pulse duration ~30 fs causes full ionization of nanoparticles and high state ionization of gold atoms and pushes out the free electrons via the ponderomotive force. The charged nanorods have an electric field that has transverse component towards the axis of symmetry and axial field outwards. Thus the nanoparticles are accelerated axially while confined transversely. Deuterium beam of a few MeV energy can be produced by this technique.

Flow behind the magnetogasdynamical cylindrical shock wave in rotating non-ideal dusty gas with monochromatic radiation

The proliferation of the cylindrical shock in non-ideal rotating gases accompanying the mixture of crystalline solids with monochromatic radiation as well as magnetic (azimuthal/axial) field is examined. The fluid velocity of ambient media is considered to contain radial, axial, and azimuthal heads. Similarity solutions are achieved. The distribution of flow variables in the medium just behind the shock for the cases of power-law shock paths are analyzed. This is worthy to note, the pressure and density at piston disintegrate in occupancy of an azimuthal magnetic field, therefore suction structures at the axis of symmetry, which is identically in accord with controlled circumstances for trying to produce shock waves.

Features of ion generation by a picosecond laser in the range of 1011 – 1013 W/cm2 power densities

Picosecond lasers (ps-lasers) have significant advantages for the generation of low charge state ions compared to nanosecond lasers because the influence of heat conductivity on a solid target is almost negligible in the case of ps-laser ablation for laser pulse durations less than 10 ps. However, there is no comprehensive data on ion yields for different elements and target irradiation conditions for laser power densities at the target surface around and below 1013 W/cm2, which is of interest to our study of such plasmas as a source of low charge state ions for various applications, particularly for external injection of those ions into an Electron Beam Ion Source (EBIS). We investigated ion generation from Al, Ti, Cu, Nb and Ta target elements by a ps-laser with power densities in the range of 1011 – 1013 W/cm2 at the target surface. A ps-laser with 1.27 mJ maximum energy within an 8 ps pulse and repetition rate up to 400 Hz has been used to generate a laser-ablated plasma. Dependencies of ion current vs time, total charge of registered ions as well as ion kinetic energy distributions are characterized using a Faraday cup. Significant difference in ion current dynamics between first, second and following shots onto the same target spot was found for all five target elements. The total charge of ions registered by the Faraday cup increases linearly with increasing laser pulse energy and is almost independent of the target element and number of shots onto the same target spot for all five target elements studied. The results obtained give us a basis for specification and design of the source of low charge state ions for external injection into EBIS.