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arXiv · 1510.08316

An all-optical Compton source for single-exposure X-ray imaging

A. Döpp·E. Guillaume·C. Thaury·J. Gautier·I. Andriyash·A. Lifschitz·J-P. Goddet·A. Tafzi·V. Malka·A. Rousse·K. Ta Phuoc
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Abstract

All-optical Compton sources are innovative, compact devices to produce high energy femtosecond X-rays. Here we present results on a single-pulse scheme that uses a plasma mirror to reflect the drive beam of a laser plasma accelerator and to make it collide with the highly-relativistic electrons in its wake. The accelerator is operated in the self-injection regime, producing quasi-monoenergetic electron beams of around 150 MeV peak energy. Scattering with the intense femtosecond laser pulse leads to the emission of a collimated high energy photon beam. Using continuum-attenuation filters we measure significant signal content beyond 100 keV and with simulations we estimate a peak photon energy of around 500 keV. The source divergence is about 13 mrad and the pointing stability is 7 mrad. We demonstrate that the photon yield from the source is sufficiently high to illuminate a centimeter-size sample placed 90 centimeters behind the source, thus obtaining radiographs in a single shot.

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A. Döpp, E. Guillaume, C. Thaury, J. Gautier, I. Andriyash, A. Lifschitz, J-P. Goddet, A. Tafzi, V. Malka, A. Rousse, K. Ta Phuoc. 2015-11-04. An all-optical Compton source for single-exposure X-ray imaging. https://doi.org/10.1088/0741-3335%2F58%2F3%2F034005

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