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arXiv · 1507.03302

Femtosecond response time measurements of a Cs2Te photocathode

A. Aryshev·M. Shevelev·Y. Honda·N. Terunuma·J. Urakawa
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Abstract

We present the response time measurements of a Cs2Te photocathode illuminated with two 100 fs duration, variable time separation laser pulses at 266 nm wavelength. The response time was confirmed in dispersive region downstream of a 12-cell standing wave S-band acceleration structure using a well-known RF zero-crossing technique. At the same time it was also measured by changing mechanical path-length difference between two micro-bunches. Both methods agree that Cs2Te photocathode time response is of the order of 250 fs and thereby it is possible to generate and control a THz sequence of relativistic electron bunches by a conventional S-band RF gun. This result further opens a possibility to construct wide-range tunable THz FEL.

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A. Aryshev, M. Shevelev, Y. Honda, N. Terunuma, J. Urakawa. 2015-07-13. Femtosecond response time measurements of a Cs2Te photocathode. https://doi.org/10.1063/1.4994224

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