Low emittance lattice for the Duke storage ring soft X-ray FEL

Laser-slicing at a diffraction-limited storage ring light source in the soft X-ray region is investigated with theoretical and numerical modelling. It turns out that the slicing efficiency is favoured by the ultra-low beam emittance, and that slicing can be implemented without interference to the standard multi-bunch operation. Spatial and spectral separation of the sub-picosecond radiation pulse from a hundreds of picosecond-long background is achieved by virtue of 1:1 imaging of the radiation source. The spectral separation is enhanced when the radiator is a transverse gradient undulator. The proposed configuration applied to the Elettra 2.0 six-bend achromatic lattice envisages total slicing efficiency as high as 10−7, one order of magnitude larger than the demonstrated state-of-the-art, at the expense of pulse durations as long as 0.4 ps FWHM and average laser power as high as ∼40 W.

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Status of a beamline for a 60‐period soft x‐ray undulator in the low emittance operation of the Photon Factory storage ring

Review of Scientific Instruments ◽

10.1063/1.1140881 ◽

1989 ◽

Vol 60 (7) ◽

pp. 1889-1892 ◽

Cited By ~ 9

Author(s):

Hideki Maezawa ◽

Akio Toyoshima ◽

Yasushi Kagoshima ◽

Kouichi Mori ◽

Tetsuya Ishikawa

Keyword(s):

Storage Ring ◽

X Ray ◽

Photon Factory ◽

Low Emittance

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Hard X-ray nanofocusing at low-emittance synchrotron radiation sources

Journal of Synchrotron Radiation ◽

10.1107/s1600577514016269 ◽

2014 ◽

Vol 21 (5) ◽

pp. 996-1005 ◽

Cited By ~ 26

Author(s):

Christian G. Schroer ◽

Gerald Falkenberg

Keyword(s):

Electron Beam ◽

Synchrotron Radiation ◽

Storage Ring ◽

Source Parameters ◽

Gaussian Model ◽

Scanning Microscopy ◽

X Ray ◽

Radiation Sources ◽

Central Cone ◽

Low Emittance

X-ray scanning microscopy relies on intensive nanobeams generated by imaging a highly brilliant synchrotron radiation source onto the sample with a nanofocusing X-ray optic. Here, using a Gaussian model for the central cone of an undulator source, the nanobeam generated by refractive X-ray lenses is modeled in terms of size, flux and coherence. The beam properties are expressed in terms of the emittances of the storage ring and the lateral sizes of the electron beam. Optimal source parameters are calculated to obtain efficient and diffraction-limited nanofocusing. With decreasing emittance, the usable fraction of the beam for diffraction-limited nanofocusing experiments can be increased by more than two orders of magnitude compared with modern storage ring sources. For a diffraction-limited storage ring, nearly the whole beam can be focused, making these sources highly attractive for X-ray scanning microscopy.

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Coherence properties of the high-energy fourth-generation X-ray synchrotron sources

Journal of Synchrotron Radiation ◽

10.1107/s1600577519013079 ◽

2019 ◽

Vol 26 (6) ◽

pp. 1851-1862 ◽

Cited By ~ 5

Author(s):

R. Khubbutdinov ◽

A. P. Menushenkov ◽

I. A. Vartanyants

Keyword(s):

Electron Beam ◽

Storage Ring ◽

High Energy ◽

Storage Rings ◽

Relative Energy ◽

Diffraction Limit ◽

Energy Spread ◽

Fourth Generation ◽

X Ray ◽

Low Emittance

An analysis of the coherence properties of the fourth-generation high-energy storage rings with emittance values of 10 pm rad is performed. It is presently expected that a storage ring with these low emittance values will reach diffraction limit at hard X-rays. Simulations of coherence properties were performed with the XRT software and an analytical approach for different photon energies from 500 eV to 50 keV. It was demonstrated that a minimum photon emittance (diffraction limit) reached at such storage rings is λ/2π. Using mode decomposition it is shown that, for the parameters of the storage ring considered in this work, the diffraction limit will be reached for soft X-ray energies of 500 eV. About ten modes will contribute to the radiation field at 12 keV photon energy and even more modes give a contribution at higher photon energies. Energy spread effects of the electron beam in a low-emittance storage ring were analysed in detail. Simulations were performed at different relative energy spread values from zero to 2 × 10−3. A decrease of the degree of coherence with an increase of the relative energy spread value was observed. This analysis shows that, to reach the diffraction limit for high photon energies, electron beam emittance should go down to 1 pm rad and below.

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