Suppression of microbunching instability in the linac coherent light source

A microbunching instability driven by longitudinal space charge, coherent synchrotron radiation, and linac wakefields is studied for the linac coherent light source (LCLS) accelerator system. Since the uncorrelated (local) energy spread of electron beams generated from a photocathode rf gun is very...

Full description

Bibliographic Details
Main Authors: Z. Huang, M. Borland, P. Emma, J. Wu, C. Limborg, G. Stupakov, J. Welch
Format: Article
Language:English
Published: American Physical Society 2004-07-01
Series:Physical Review Special Topics. Accelerators and Beams
Online Access:http://doi.org/10.1103/PhysRevSTAB.7.074401
Description
Summary:A microbunching instability driven by longitudinal space charge, coherent synchrotron radiation, and linac wakefields is studied for the linac coherent light source (LCLS) accelerator system. Since the uncorrelated (local) energy spread of electron beams generated from a photocathode rf gun is very small, the microbunching gain may be large enough to significantly amplify rf-gun generated modulations or even shot-noise fluctuations of the electron beam. The uncorrelated energy spread can be increased by an order of magnitude to provide strong Landau damping against the instability without degrading the free-electron laser performance. We study different damping options in the LCLS and discuss an effective laser heater to minimize the impact of the instability on the quality of the electron beam.
ISSN:1098-4402