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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.
High gradient quadrupoles are necessary for different applications such as laser plasma acceleration, colliders, and diffraction limited light sources. Permanent magnet quadrupoles provide a higher field strength and compactness than conventional ele
A compact adjustable focusing system for a 2 MeV H- RFQ Linac is designed, constructed and tested based on four permanent magnet quadrupoles (PMQ). A PMQ model is realised using finite element simulations, providing an integrated field gradient of 2.
Cold atom electron sources are a promising alternative to traditional photocathode sources for use in ultrafast electron diffraction due to greatly reduced electron temperature at creation, and the potential for a corresponding increase in brightness
We describe the construction of a prototype hybrid permanent magnet dipole and quadruple. The magnet consists of two concentric rings of SmCo magnetic material 5 cm in length. The outer ring is made of 16 uniformly magnetized blocks assembled as a Ha
In the past decade, the bunch lengths of electrons in accelerators have decreased dramatically to the range of a few picoseconds cite{Uesaka94,Trotz97}. Measurement of the length as well as the longitudinal profile of these short bunches have been a