View of the experimental platform of branch 2 at beamline P04.
The Variable Polarization XUV beamline P04 at PETRA III enables new classes of experiments with soft X-rays in the fields of gas phase physics, magnetic spectroscopy, high resolution photoelectron spectroscopy, surface chemistry, soft X-ray diffraction and holography.
The unique characteristics of this beamline are an exceptionally high photon flux – up to several 10E+12 photons per second – in a very small bandpass (resolving power exceeds 10,000) as well as variable polarization properties over a very wide energy range (250-3000 eV) using only the first harmonic of an APPLE-2 type undulator.
Due to the very low emittance of the PETRA III storage ring the radiation of the beamline is practically diffraction limited in whole photon energy range except for the horizontal source size (300 µm FWHM).
If you have any questions or suggestions, please contact the beamline scientist in charge (Moritz Hoesch).
Attention! Please be aware of the vacuum guidelines for DESY. Especially take a look at the allowed materials. Here, you can find further Information for your beamtime! We recommend you to read the P04 Manual (pdf, 967KB) in advance!
P04 Manual
Some explanations
Extreme ultraviolet = The range of electro-magnetic waves between 0.2 and 100 nanometers (according to James A.R. Samson, Techniques of Vacuum Ultraviolet Spectroscopy, Glasgow 1967)
Insertion device = For this beamline the insertion device will be a variable polarization undulator, a special magnet structure forcing charged particles on a slalom- or cork-screw-like track thus inducing them to emit a most intensive light beam having a well defined state of polarization.
First harmonic = The lowest possible light frequency (and thus the energy) at which the undulator emits light along the on-axis direction.
