Narrow band X-ray emission in the water-window spectral region from a laser heated gold copper mix-Z plasma

摘要

A laser plasma X-ray source of narrow spectral range in the water-window region, is reported using a 50-50 (atomic fraction) mixture of gold-copper mix-Z planar target. Plasma was produced using the second harmonic beam of an Nd:glass laser focused to an intensity ～ 10~(13) W/cm~2 on the target. The spectrum of the plasma radiation transmitted through a free-standing 0.4 μm aluminium/0.9 μm vanadium X-ray filter foil was measured to lie in the narrow-band of 24-26 A. This provides a debris-free X-ray dose of 2-3 mJ/sr which can be used for single shot X-ray imaging of live biological samples.