Characteristic X-rays generation under the action of femtosecond laser pulses on nano-structured targets

Enhancement of K-alpha yield from a metal foil covered with metal rods of submicron sizes, with low aspect ratio, irradiated by a p-polarized femtosecond laser pulses of about 10(17) W/cm(2) intensity is demonstrated. Obtained relative increase in K-alpha X-ray line emission is explained with a model of vacuum heating of fast electrons.