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arXiv · 1605.01448

High efficiency energy extraction from a relativistic electron beam in a strongly tapered undulator

Nicholas Sudar·Pietro Musumeci·Joe Duris·Ivan Gadjev·Mikhail Polyaniy·Igor Pogorelsky·Mikhail Fedurin·Christina Swinson·Marcus Babzien·Karl Kusche·Avi Gover
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Abstract

We present results of an experiment where, using a 200 GW CO2 laser seed, a 65 MeV electron beam was decelerated down to 35 MeV in a 54 cm long strongly tapered helical magnetic undulator, extracting over 30$\%$ of the initial electron beam energy to coherent radiation. These results demonstrate unparalleled electro-optical conversion efficiencies for a relativistic beam in an undulator field and represent an important step in the development of high peak and average power coherent radiation sources.

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Nicholas Sudar, Pietro Musumeci, Joe Duris, Ivan Gadjev, Mikhail Polyaniy, Igor Pogorelsky, Mikhail Fedurin, Christina Swinson, Marcus Babzien, Karl Kusche, Avi Gover. 2016-05-04. High efficiency energy extraction from a relativistic electron beam in a strongly tapered undulator. https://doi.org/10.1103/physrevlett.117.174801

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