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

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 نشر من قبل David Cesar
 تاريخ النشر 2016
  مجال البحث فيزياء
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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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