FineEstBeAMS beamline is equipped with the following attributes:
| Techniques | X-ray Photoelectron Spectroscopy (XPS), X-ray Absorption Spectroscopy (XAS), Photoelectron Photoion Coincidence Spectroscopy (PEPICO), Time-of Flight Mass Spectroscopy (TOF), Photoluminescence Spectroscopy (PS) |
| Beam Size | 0.2 (V) x 0.2 (H) mm, best: 0.05 (V) x 0.05 (H) mm |
| Energy Range | 4.5 - 1300 eV (275 - 0.95 nm) |
| Time Scales | nanoseconds to seconds |
| Samples | Atomis, Molecules, Clusters, Gases, Liquids, Atmospheric particles, Nanoparticles, Solids, Surfaces and Interfaces |
The radiation source is an elliptically polarizing undulator. It can provide radiation with different polarization properties: linearly polarized (horizontal, vertical, or inclined direction) and circularly polarized. Only linear horizontal and vertical polarizations have been tested extensively.
The photon energy range extends from 4.5 eV to about 1300 eV and is covered by two gratings. A 92 lines/mm grating can be used from 4.5 eV to 50 eV, while a 600 lines/mm grating works above 15 eV. However, the photon flux decreases considerably toward high photon energies. The actually usable photon energy range depends on the nature of particular experiments.
The beamline has achieved a resolving power of about 11000 at 400 eV photon energy using the exit slit of ~10 um in the monochromator.
A more detailed description of the beamline performance can be found in the Beamline optics page
Capabilities available for users
FinEstBeAMS has three operational end stations: Gas-phase end station (GPES), Photoluminescence end station (PLES), and Solid-state end station (SSES).
The GPES has been designed to detect coincidences between energy resolved electrons and positive ions (PEPICO), but single electron and ion time-of-flight spectra can, of course, be measured. A setup consisting of two ion TOF spectrometers is also available. It can be used to measure coincidences between negative ions and positive ions. A magnetic bottle electron spectrometer can be requested for experiments in single-bunch operation but its use requires collaboration with the NANOMO research group from the University of Oulu (Finland).
The PLES can be used to measure fluorescence emission from different kinds of solids in the infra-red, visible and ultraviolet spectral ranges. The excitation functions of these emissions can be determined by scanning the incident photon energy.
The SSES is now available to regular users for studies of atomic and electronic structure of bulk and surface materials. It has been designed as a high-throughput workhorse for XPS, ARPES, and XAS with flexible sample preparation options. The temperature of sample preparation can be around 95 K by liquid-nitrogen cooling and up to around 1300 K by resistive heating, direct heating and e-beam heating. The temperature of sample during measurement can be around 95 K by liquid-nitrogen cooling and 55 K by liquid-helium cooling, and from room temperature to to 600 K by resistive heating.
Further information about the end stations can be found under submenu “Experimental stations”.
Single-bunch operation
There will be a whole week of single-bunch (SB) operation in the period March – July 2024. If you want to apply for a beamtime with SB operation only, you should indicate it clearly in your beamtime proposal. Please note that the FinEstBeAMS beamline has no chopper.
It might also be possible to arrange some SB shifts outside of the SB week if other beamlines at the 1.5 GeV ring agree with it. Please express your interest in combining SB shifts with your (multi-bunch) proposal by checking the corresponding box as a detector under the selection of the end station (available for the PLES and GPES) and motivate the need in your beamtime proposal.
Fast Access proposals
FinEstBeAMS accepts Fast Access proposals to allow very short experiments or feasibility tests to be done on a short notice. The access mode is only available for the SSES. Fast access proposals can be submitted any time. Maximum 6 shifts (24 hrs) can be allocated for a single proposal. In the fall 2023 semester, fast-access proposals can be scheduled on the following days: October 4 (already reserved), December 13, and February 27. Information about different kinds of fast access proposals can be found here.