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Title: Demonstration of cathode emittance dominated high bunch charge beams in a DC gun-based photoinjector

Abstract

We present the results of transverse emittance and longitudinal current profile measurements of high bunch charge (≥100 pC) beams produced in the DC gun-based Cornell energy recovery linac photoinjector. In particular, we show that the cathode thermal and core beam emittances dominate the final 95% and core emittances measured at 9–9.5 MeV. Additionally, we demonstrate excellent agreement between optimized 3D space charge simulations and measurement, and show that the quality of the transverse laser distribution limits the optimal simulated and measured emittances. These results, previously thought achievable only with RF guns, demonstrate that DC gun based photoinjectors are capable of delivering beams with sufficient single bunch charge and beam quality suitable for many current and next generation accelerator projects such as Energy Recovery Linacs and Free Electron Lasers.

Authors:
; ; ; ;  [1]
  1. CLASSE, Cornell University, 161 Synchrotron Drive Ithaca, New York 14853-8001 (United States)
Publication Date:
OSTI Identifier:
22412786
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 106; Journal Issue: 9; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; BEAM BUNCHING; BEAM EMITTANCE; BEAM INJECTION; BEAM PRODUCTION; BEAM PROFILES; CATHODES; FREE ELECTRON LASERS; LINEAR ACCELERATORS; MEV RANGE; SPACE CHARGE

Citation Formats

Gulliford, Colwyn, E-mail: cg248@cornell.edu, Bartnik, Adam, E-mail: acb20@cornell.edu, Bazarov, Ivan, Dunham, Bruce, and Cultrera, Luca. Demonstration of cathode emittance dominated high bunch charge beams in a DC gun-based photoinjector. United States: N. p., 2015. Web. doi:10.1063/1.4913678.
Gulliford, Colwyn, E-mail: cg248@cornell.edu, Bartnik, Adam, E-mail: acb20@cornell.edu, Bazarov, Ivan, Dunham, Bruce, & Cultrera, Luca. Demonstration of cathode emittance dominated high bunch charge beams in a DC gun-based photoinjector. United States. doi:10.1063/1.4913678.
Gulliford, Colwyn, E-mail: cg248@cornell.edu, Bartnik, Adam, E-mail: acb20@cornell.edu, Bazarov, Ivan, Dunham, Bruce, and Cultrera, Luca. 2015. "Demonstration of cathode emittance dominated high bunch charge beams in a DC gun-based photoinjector". United States. doi:10.1063/1.4913678.
@article{osti_22412786,
title = {Demonstration of cathode emittance dominated high bunch charge beams in a DC gun-based photoinjector},
author = {Gulliford, Colwyn, E-mail: cg248@cornell.edu and Bartnik, Adam, E-mail: acb20@cornell.edu and Bazarov, Ivan and Dunham, Bruce and Cultrera, Luca},
abstractNote = {We present the results of transverse emittance and longitudinal current profile measurements of high bunch charge (≥100 pC) beams produced in the DC gun-based Cornell energy recovery linac photoinjector. In particular, we show that the cathode thermal and core beam emittances dominate the final 95% and core emittances measured at 9–9.5 MeV. Additionally, we demonstrate excellent agreement between optimized 3D space charge simulations and measurement, and show that the quality of the transverse laser distribution limits the optimal simulated and measured emittances. These results, previously thought achievable only with RF guns, demonstrate that DC gun based photoinjectors are capable of delivering beams with sufficient single bunch charge and beam quality suitable for many current and next generation accelerator projects such as Energy Recovery Linacs and Free Electron Lasers.},
doi = {10.1063/1.4913678},
journal = {Applied Physics Letters},
number = 9,
volume = 106,
place = {United States},
year = 2015,
month = 3
}
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