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arXiv · 0909.3440

Controlling the spectrum of x-rays generated in a laser-plasma accelerator by tailoring the laser wavefront

S. P. D. Mangles·G. Genoud·S. Kneip·M. Burza·K. Cassou·B. Cros·N. P. Dover·C. Kamperidis·Z. Najmudin·A. Persson·J. Schreiber·F. Wojda·C. G. Wahlstrom
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Abstract

By tailoring the wavefront of the laser pulse used in a laser-wakefield accelerator, we show that the properties of the x-rays produced due to the electron beam's betatron oscillations in the plasma can be controlled. By creating a wavefront with coma, we find that the critical energy of the synchrotron-like x-ray spectrum can be significantly increased. The coma does not substantially change the energy of the electron beam, but does increase its divergence and produces an energy-dependent exit angle, indicating that changes in the x-ray spectrum are due to an increase in the electron beam's oscillation amplitude within the wakefield.

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S. P. D. Mangles, G. Genoud, S. Kneip, M. Burza, K. Cassou, B. Cros, N. P. Dover, C. Kamperidis, Z. Najmudin, A. Persson, J. Schreiber, F. Wojda, C. G. Wahlstrom. 2009-09-18. Controlling the spectrum of x-rays generated in a laser-plasma accelerator by tailoring the laser wavefront. https://doi.org/10.1063/1.3258022

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