Production of K-$\alpha$ Emission X-Rays from Laser Solid Interactions for use in Phase Contrast Imaging

Phase contrast X-ray imaging represents significant potential for radiographical medical applications. The relativistic lamba cubed laser at the University of Michigan produces 30 fs laser pulses at a peak intensity of $5\times10^{18} W/cm^{2}$. When focused onto solid targets, the resulting plasma formation produces small source size and monochromatic K-$\alpha$ X-rays well suited to the purpose of imaging, since the spatial coherence of the X-ray source is inversely dependent on source size. In addition, the laser's repetition rate of 500 Hz allows long time scale production of the X-rays. Currently work is underway to accurately measure the X-ray source size, which will precisely determine the spatial coherence of the X-ray pulses. Radiographic images will then be taken with a range of coated and uncoated metal laser targets and studied for phase contrast characteristics.