Abstract
Profiling structured beams produced by X-ray free-electron lasers (FELs) is crucial to both maximizing signal intensity for weakly scattering targets and interpreting their scattering patterns. Earlier ablative imprint studies describe how to infer the X-ray beam profile from the damage that an attenuated beam inflicts on a substrate. However, the beams in-situ profile is not directly accessible with imprint studies because the damage profile could be different from the actual beam profile. On the other hand, although a Shack-Hartmann sensor is capable of in-situ profiling, its lenses may be quickly damaged at the intense focus of hard X-ray FEL beams. We describe a new approach that probes the in-situ morphology of the intense FEL focus. By studying the translations in diffraction patterns from an ensemble of randomly injected sub-micron latex spheres, we were able to determine the non-Gaussian nature of the intense FEL beam at the Linac Coherent Light Source (SLAC National Laboratory) near the FEL focus. We discuss an experimental application of such a beam-profiling technique, and the limitations we need to overcome before it can be widely applied.
Original language | English (US) |
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Title of host publication | X-Ray Free-Electron Lasers |
Subtitle of host publication | Beam Diagnostics, Beamline Instrumentation, and Applications |
Volume | 8504 |
DOIs | |
State | Published - Dec 1 2012 |
Externally published | Yes |
Event | X-Ray Free-Electron Lasers: Beam Diagnostics, Beamline Instrumentation, and Applications - San Diego, CA, United States Duration: Aug 13 2012 → Aug 16 2012 |
Other
Other | X-Ray Free-Electron Lasers: Beam Diagnostics, Beamline Instrumentation, and Applications |
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Country | United States |
City | San Diego, CA |
Period | 8/13/12 → 8/16/12 |
Keywords
- Aerosols
- Beam diagnostics
- Beam profiling
- Diffraction
- Hartmann sensor
- Imaging
- LCLS
- X-ray freeelectron laser
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Computer Science Applications
- Applied Mathematics
- Electrical and Electronic Engineering