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arXiv · 1210.0717

Quasi-monoenergetic electron beams production in a sharp density transition

S. Fourmaux·K. Ta Phuoc·P. Lassonde·S. Corde·G. Lebrun·V. Malka·A. Rousse·J. C. Kieffer
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Abstract

Using a laser plasma accelerator, experiments with a 80 TW and 30 fs laser pulse demonstrated quasi-monoenergetic electron spectra with maximum energy over 0.4 GeV. This is achieved using a supersonic He gas jet and a sharp density ramp generated by a high intensity laser crossing pre-pulse focused 3 ns before the main laser pulse. By adjusting this crossing pre-pulse position inside the gas jet, among the laser shots with electron injection more than 40% can produce quasi-monoenergetic spectra. This could become a relatively straight forward technique to control laser wakefield electron beams parameters.

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S. Fourmaux, K. Ta Phuoc, P. Lassonde, S. Corde, G. Lebrun, V. Malka, A. Rousse, J. C. Kieffer. 2012-10-02. Quasi-monoenergetic electron beams production in a sharp density transition. https://doi.org/10.1063/1.4752114

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