PETRA III (Hamburg)

PETRA III is the worldwide most brilliant storage ring based X-ray sources for high energy photons providing a brilliance exceeding 1021 ph/(s mm2 mrad2 0.1% BW). It operates at 6 GeV particle energy and provides a horizontal and vertical emittance of 1.2 nmrad x 0.01 nmrad at photon energies between 150 eV and 200 keV depending on the beamline. PETRA III runs at 100 mA beam current in top-up mode keeping the photon flux stable with 1% and provides 5000 h X-ray beam per year for user operation. The vertical beam parameters of PETRA III are close to the diffraction limit and hence are very similar to other high-energy 3rd generation sources. However, today the horizontal emittance of 1.2 nm rad is 3 – 4 times smaller at PETRA III compared to any other high-energy (6 GeV and higher) storage ring in the world, which makes PETRA III a unique synchrotron light source.