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arXiv · 1808.07846

Micro-bunching for generating tunable narrow-band THz radiation at the FAST photoinjector

J. Hyun·P. Piot·T. Sen·J. C. Thangaraj
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Abstract

This paper presents expected THz radiation spectra emitted by micro-bunched electron beams produced using a slit-mask placed within a magnetic chicane in the FAST (Fermilab Accelerator Science and Technology) electron injector at Fermilab. Our purpose is to generate tunable narrow-band THz radiation with a simple scheme in a conventional photo-injector. Using the slit-mask in the chicane, we create a longitudinally micro-bunched beam after the chicane by transversely slicing an energy chirped electron bunch at a location with horizontal dispersion. In this paper, we discuss the theory related to the micro-bunched beam structure, the beam optics, the simulation results of the micro-bunched beam and the bunching factors. Energy radiated at THz frequencies from two sources: coherent transition radiation and from a wiggler is calculated and compared. We also discuss the results of a simple method to observe the micro-bunching on a transverse screen monitor using a skew quadrupole placed in the chicane.

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J. Hyun, P. Piot, T. Sen, J. C. Thangaraj. 2018-08-23. Micro-bunching for generating tunable narrow-band THz radiation at the FAST photoinjector. https://doi.org/10.1016/j.nima.2018.10.219

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