Inverse Free Electron Laser Heater for the LCLS

Conference · Wed May 11 04:00:00 EDT 2005

OSTI ID:890855

Bentson, L D; Bolton, P; Carr, R; Dowell, D; Emma, P; Gilevich, S; Huang, Z; Welch, J J; Wu, J

The Linac Coherent Light Source (LCLS) free electron laser employs an RF photocathode gun that yields a 1nC bunch a few picoseconds long, which must be further compressed to yield the high current required for Self Amplified Spontaneous Emission (SASE) gain. The electron beam from the RF photocathode gun is quite sensitive to microbunching instabilities such as coherent synchrotron radiation (CSR) in the compressor chicanes and longitudinal space charge (LSC) in the linac. These effects can be Landau damped by adding energy spread to the electron bunch prior to compression. They propose to do this by co-propagating an infrared laser beam with the electron bunch in an undulator in the LCLS injector beamline. The undulator is placed in a four bend magnet chicane to allow the Ir laser beam to propagate colinearly with the e-beam while it oscillates in the undulator. The IR laser beam is derived from the photocathode gun drive laser, so the two beams are synchronized. Simulations presented elsewhere in these proceedings show that the laser interaction damps the microbunching instabilities to a very great extent. This paper is a description of the design of the laser heater.

• Research Organization: Stanford Linear Accelerator Center (SLAC)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-76SF00515
• OSTI ID: 890855
• Report Number(s): SLAC-PUB-11186
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ACCELERATORS
Accelerators
HEPEX
COMPRESSION
COMPRESSORS
ELECTRON BEAMS
ELECTRONS
FREE ELECTRON LASERS
HEATERS
LASERS
LIGHT SOURCES
LINEAR ACCELERATORS
MAGNETS
PHOTOCATHODES
SPACE CHARGE
SYNCHROTRON RADIATION
WIGGLER MAGNETS