PHELIX is a beamline operating in the soft X-ray range, the source of which is an elliptically polarizing undulator. Owing to the use of such a source, the beamline produces both linear and circular or elliptical polarizations of high intensity light. The light parameters of the PHELIX beamline and the equipment available at the end-station allow for spectroscopic measurements of photoelectrons and absorption in ultra-high vacuum conditions.

The available energy range of radiation (50 - 1500 eV) is suitable for research on many materials used e.g. in modern electronic devices, modern catalysts or fuel cells. The end-station enables measurements of Resonant Photoemission (Res-PES), Circular Dichroism (CD), X-ray Absorption Spectroscopy (XAS) in the Total Fluorescence Yield (TFY) mode and measurement of the sample current (Total Electron Yield - TEY). However, what makes the end-station unique is the ability to map the band structure in three dimensional k space using the Soft X-ray Angle Resolved Photoelectron Spectroscopy (SX-ARPES) and obtaining direct information about the spin texture using the 3D spin detector integrated with a photoelectron spectrometer (Spin Resolved Angle Resolved Photoelectron Spectroscopy - SR-ARPES).

Beamline parameters

Parameters:	Value:
Source	Elliptically polarizing undulator EPU APPLE II type
Available energy range	40–1500 eV for horizontal polarization 50–1500 eV for vertical polarization 40–350 eV for circular polarization (100%) 50-1035 eV for elliptical (50%)
Energy resolution ΔE/E	10 000
Beam size at sample (H x V)	30x80 µm2 @ 50 eV  10x60 µm2 @ 1500 eV
Photon flux at sample	8.2×1012 ph/s @ 50 eV 1.4×1012 ph/s  @ 1500 eV RP = 10 000, electron, current = 500 mA
Polarization	Linear (horizontal, vertical), circular, elliptical
End station	PHELIX