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Generation of angular-momentum-dominated electron beams from a photoinjector

Y. -E Sun·P. Piot·K. -J. Kim·N. Barov·S. Lidia·J. Santucci·R. Tikhoplav·J. Wennerberg
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Abstract

Various projects under study require an angular-momentum-dominated electron beam generated by a photoinjector. Some of the proposals directly use the angular-momentum-dominated beams (e.g. electron cooling of heavy ions), while others require the beam to be transformed into a flat beam (e.g. possible electron injectors for light sources and linear colliders). In this paper, we report our experimental study of an angular-momentum-dominated beam produced in a photoinjector, addressing the dependencies of angular momentum on initial conditions. We also briefly discuss the removal of angular momentum. The results of the experiment, carried out at the Fermilab/NICADD Photoinjector Laboratory, are found to be in good agreement with theoretical and numerical models.

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Y. -E Sun, P. Piot, K. -J. Kim, N. Barov, S. Lidia, J. Santucci, R. Tikhoplav, J. Wennerberg. 2004-11-06. Generation of angular-momentum-dominated electron beams from a photoinjector. https://doi.org/10.1103/physrevstab.7.123501

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