UV Laser Pulse Temporal Profile Requirements for the LCLS Injector - Part I - Fourier Transform Limit for a Temporal Zero Slope Flattop
The temporal profile of the uv drive laser pulse for the LCLS injector is specified by the duration, the rise/fall time, and the maximum rms amplitude (for all frequencies) of residual modulation in the plateau region. The bandwidth of the uv laser system should accommodate pulses with a rise/fall time as low as 0.7 ps and an rms residual amplitude modulation (on the plateau) below 0.5% in the absence of a laser heater. Computations including the laser heater [3] relax this requirement to the 5% level. Numerical analyses of Fourier transform limited uv pulses show that the extent of frequency sidebands should extend to at least 1.5 THz on either side of the central uv frequency. For simplicity, we assume that the emitted electron beam profile matches the laser profile. The evolution of those electron beam distributions in the longitudinal phase space along the beamline as calculated with PARMELA/ASTRA are shown. Related spectral and shaping requirements on the fundamental ir pulses are briefly addressed.
- Research Organization:
- SLAC National Accelerator Lab., Menlo Park, CA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- AC02-76SF00515
- OSTI ID:
- 839672
- Report Number(s):
- SLAC-TN-05-012; TRN: US0503320
- Country of Publication:
- United States
- Language:
- English
Similar Records
UV Laser Pulse Temporal Profile Requirements for the LCLS Injector - Part I - Fourier Transform Limit for a Temporal Zero Slope Flattop
Temporal Profile of the LCLS Photocathode Ultraviolet Drive Laser Tolerated by the Microbunching Instability