Study of supra-thermal electrons and K-{alpha} x-rays from high intensity 500 fs laser-produced plasmas

We describe recent laser-solid interaction experiments using the 500 fs Janus Nd:glass (1053 nm) laser presently at 1.5 TW power level. The laser beam path is enclosed in vacuum from the compressor to the target and is focused using an off-axis paraboloid. Optical diagnostics monitor the near field pattern, focal spot, spectrum, temporal shape and pre-pulse level. A 12 {mu}m diameter (FWHM) focal spot is achieved (2.5 {times} diffraction limit) corresponding to a peak irradiance of 8 {times} 1017 W cm{sup {minus}2} on target. A suite of x-ray diagnostics characterize the x-ray emission from the plasma. We present results for normal incidence irradiation of high-Z (Zn, Ge, Mo, Sn) solid targets. The supra-thermal electrons produced in the short scale length plasma have temperature T{sub H} > 100 keV and can efficiently fluoresce the cold K-{alpha} lines in the 8--30 keV energy range