High intensity femtosecond laser pulses can be used to generate X-ray radiation. In the laser wakefield process, when a high intensity laser pulse (<10¹⁸ W/cm²) is focused onto a gas jet target, it interacts with the instantaneously created under-dense plasma and excites a wakefield wave. In the wakefield electrons are trapped and accelerated to high energies in short distances. The electrons trapped in the wakefield can perform Betatron oscillations across the propagation axis and emit X-ray photons. The Betatron X-ray beam is broadband as the radiation emission has a synchrotron distribution. The X-ray beam is collimated and its pulse duration is femtosecond. For high resolution and phase contrast X-ray imaging applications, the important feature of the X-ray Betatron beam is the μm source size. Using ALLS 100 TW class laser system we demonstrate that the Betatron X-ray beam is both energetic and bright enough to produce single laser shot phase contrast imaging of complex objects located in air.

Date Published: 24 October 2012
PDF: 9 pages
Proc. SPIE 8412, Photonics North 2012, 841211 (24 October 2012); doi: 10.1117/12.2001554

Published in SPIE Proceedings Vol. 8412:
Photonics North 2012
Jean-Claude Kieffer, Editor(s)