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arXiv · 1604.00973

Demonstration of single-shot picosecond time-resolved MeV electron imaging using a compact permanent magnet quadrupole based lens

D. Cesar·J. Maxson·P. Musumeci·Y. Sun·J. Harrison·P. Frigola·F. H. O'Shea·H. To·D. Alesini·R. K. Li
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Abstract

We present the results of an experiment where a short focal length (~ 1.3 cm) permanent magnet electron lens is used to image micron-size features of a metal sample in a single shot, using an ultra- high brightness ps-long 4 MeV electron beam from a radiofrequency photoinjector. Magnifcation ratios in excess of 30x were obtained using a triplet of compact, small gap (3.5 mm), Halbach-style permanent magnet quadrupoles with nearly 600 T/m field gradients. These results pave the way to- wards single shot time-resolved electron microscopy and open new opportunities in the applications of high brightness electron beams.

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D. Cesar, J. Maxson, P. Musumeci, Y. Sun, J. Harrison, P. Frigola, F. H. O'Shea, H. To, D. Alesini, R. K. Li. 2016-04-04. Demonstration of single-shot picosecond time-resolved MeV electron imaging using a compact permanent magnet quadrupole based lens. https://doi.org/10.1103/physrevlett.117.024801

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