Weak FEL Gain Detection with a Modulated Laser-Based Beam Heater

Conference · Wed May 25 00:00:00 EDT 2005

OSTI ID:890808

Emma, P; Huang, Z; Wu, J

For an x-ray free-electron laser (FEL) such as the LCLS, the FEL gain signal is accompanied by spontaneous radiation with a significant power level. Detecting the weak FEL gain among the large spontaneous background in the early stage of the exponential growth or for a low quality electron beam is important in commissioning the FEL. In this paper, we describe a simple ''lock-in'' method of weak FEL gain detection, suggested by K. Robinson, accomplished by slowly modulating the laser power of a designated beam heater that controls the local energy spread of the electron beam. We present numerical modeling that shows the effectiveness of this method and discuss its implementation in the LCLS.

• Research Organization: SLAC National Accelerator Lab., Menlo Park, CA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-76SF00515
• OSTI ID: 890808
• Report Number(s): SLAC-PUB-11242; TRN: US0604804
• Resource Relation: Conference: Contributed to Particle Accelerator Conference (PAC 05), Knoxville, Tennessee, 16-20 May 2005
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ACCELERATORS
COMMISSIONING
DETECTION
ELECTRON BEAMS
FREE ELECTRON LASERS
HEATERS
IMPLEMENTATION
LASERS
RADIATIONS
SIMULATION
Accelerators
ACCPHY