Coherence Properties of Individual Femtosecond Pulses of an X-ray Free-Electron Laser
Measurements of the spatial and temporal coherence of single, femtosecond x-ray pulses generated by the first hard x-ray free-electron laser, the Linac Coherent Light Source, are presented. Single-shot measurements were performed at 780 eV x-ray photon energy using apertures containing double pinholes in 'diffract-and-destroy' mode. We determined a coherence length of 17 {micro}m in the vertical direction, which is approximately the size of the focused Linac Coherent Light Source beam in the same direction. The analysis of the diffraction patterns produced by the pinholes with the largest separation yields an estimate of the temporal coherence time of 0.55 fs. We find that the total degree of transverse coherence is 56% and that the x-ray pulses are adequately described by two transverse coherent modes in each direction. This leads us to the conclusion that 78% of the total power is contained in the dominant mode.
- 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:
- 1042676
- Report Number(s):
- SLAC-PUB-14988; PRLTAO; TRN: US1202805
- Journal Information:
- Physical Review Letters, Vol. 107, Issue 14; ISSN 0031-9007
- Country of Publication:
- United States
- Language:
- English
Similar Records
Ultra-Short Electron Bunch and X-Ray Temporal Diagnostics with an X-Band Transverse Deflector
Single shot spatial and temporal coherence properties of the SLAC linac coherent light source in the hard x-ray regime