Diffraction-limited storage ring explained

Diffraction-limited storage rings (DLSR), or ultra-low emittance storage rings, are synchrotron light sources where the emittance of the electron-beam in the storage ring is smaller or comparable to the emittance of the x-ray photon beam they produce at the end of their insertion devices.These facilities operate in the soft to hard x-ray range (100eV—100keV) with extremely high brilliance (in the order of 10²¹—10²² photons/s/mm²/mrad²/0.1%BW)

Together with X-ray free-electron lasers, they constitute the fourth generation of light sources,^[1] characterized by a relatively high coherent flux (in the order of 10¹⁴—10¹⁵photons/s/0.1%BW for DLSR) and enable extended physical and chemical characterizations at the nano-scale.

Existing diffraction-limited storage rings

• MAX IV Laboratory, in Lund, Sweden.
• Sirius, in Campinas, Brazil
• European Synchrotron Radiation Facility, Extremely Brilliant Source (ESRF-EBS), in Grenoble, France

DLSR upgrade or facilities under construction

• Advanced Photon Source Upgrade (APS-U), in Argonne, Illinois, USA
• Swiss Light Source 2, Upgrade (SLS 2.0^[2]), in Villigen, Switzerland

Planned or projected DLSR upgrades or new facilities

Upgrades

• PETRA IV, Upgrade (PETRA IV), at DESY, Hamburg, Germany
• Advanced Light Source, Upgrade (ALS-U), in Berkeley, California, USA
• Diamond II (Diamond II), in Didcot, Oxfordshire, UK
• ELETTRA 2.0 (Elettra 2.0), in Trieste, Italy
• ALBA II, in Barcelona, Spain^[3]
• SOLEIL II, in Saint-Aubin, France^[4]

New facilities

• High Energy Photon Source (HEPS), in Beijing, China^{[5] [6]}

See also

• X-Ray Free Electron Lasers

Notes and References

1. 10.1038/nphoton.2016.251. The next ten years of X-ray science. Nature Photonics. 11. 12–14. 2017. Yabashi. Makina. Tanaka. Hitoshi.
2. 10.1107/S1600577518002722. 29714174. 5929351. SLS-2 – the upgrade of the Swiss Light Source. Journal of Synchrotron Radiation. 25. 3. 631–641. 2018. Streun. Andreas. Garvey. Terence. Rivkin. Lenny. Schlott. Volker. Schmidt. Thomas. Willmott. Philip. Wrulich. Albin.
3. https://www.albasynchrotron.es/en/media/news/alba-initiates-its-upgrade-process-to-become-a-4th-generation-facility Alba Initiates Its Upgrade Process To Become A 4th Generation Facility
4. Conceptual Design Report for SOLEIL Upgrade, accessed 24 April 2023.
5. Web site: 2019-08-15 . China's next big thing: a new fourth-generation synchrotron facility in Beijing . 2023-09-15 . Physics World . en-GB.
6. Web site: 2019 . Groundbreaking Ceremony at the High Energy Photon Source in Beijing . Synchrotron Radiation News . 32:5, 40-40.