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arXiv · 1611.01701

Direct measurement of sub-10 fs relativistic electron beams with ultralow emittance

Jared Maxson·David Cesar·Giacomo Calmasini·Alexander Ody·Pietro Musumeci·David Alesini
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Abstract

Ultralow emittance ($\leq20$ nm, normalized) electron beams with $10^5$ electrons per bunch are obtained by tightly focusing an ultrafast ($\sim$ 100 fs) laser pulse on the cathode of a 1.6 cell radiofrequency photoinjector. Taking advantage of the small initial longitudinal emittance, a downstream velocity bunching cavity is used to compress the beam to $<10$ fs rms bunch length. The measurement is performed using a thick high voltage deflecting cavity which is shown to be well-suited to measure ultrashort durations of bunching beams, provided that the beam reaches a ballistic longitudinal focus at the cavity center.

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Jared Maxson, David Cesar, Giacomo Calmasini, Alexander Ody, Pietro Musumeci, David Alesini. 2017-03-10. Direct measurement of sub-10 fs relativistic electron beams with ultralow emittance. https://doi.org/10.1103/physrevlett.118.154802

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