The UARPES beamline at SOLARIS has given its first light
5th May 2016 - Krakow - Poland

The first light from the variably polarizing undulator (APPLE II type) installed on the UARPES beamline at the SOLARIS synchrotron in Krakow, has been observed. This is a major step towards making UARPES beamline available for scientists.

The "footprint" of the synchrotron "light" (ultraviolet of the photon energy 140 eV) on a luminescent YAG screen. In the image can be seen: a central spot of the size of about 5 mm in diameter and a ring of 6 mm radius. They were measured at an effective distance of 16 m from the source. They correspond perfectly to the theoretically predicted diffracted beams of the undulator fundamental harmonic radiation. The electron energy is 1.5 GeV and the undulator gap is 100mm. For these settings it is expected that the 0-order diffraction beam appears circularly symmetric and with a divergence of 0.12 mRad FWHM while the 1-order diffraction ring is observed 0.37 mRad away from the beam axis.
Photo: Jacek Kołodziej


Photo: SOLARIS Team

The elliptically polarizing, APPLE-II type undulator is a radiation source. Angle-resolved photoelectron spectroscopy (ARPES) allows the measurement of basic quantities, i.e. the energy and momentum, describing a photoelectron state in the space outside a solid sample. The importance of the ARPES technique for contemporary science and technology is widely recognized. Dedicated ARPES beamlines exist at almost all synchrotron radiation centers worldwide.