BL29 BOREAS
Beamline fOr REsonant Absorption and Scattering
The variable polarization soft X-ray beamline is dedicated to polarization dependent spectroscopy (absorption and scattering). It will be equipped with two end-stations for magnetic dichroism (XMCD/XMLD) and resonant soft X-ray scattering (RSXS).
NEWS
16/12/2011The first XMCD spectrum has been measured at the Fe L2,3 edges and is shown here
28/10/2011This week we have been optimizing the focal spot of the beam reflected by PM and TM onto the entrance slit, with some (partial) success
20/10/2011After the first 24 hours with x-ray beam (eight hours per day) the first rough alignment of the beamline is completed and the beam reaches the gas cell, the last element available under UHV (some pictures of the beam are available here). The first XAS test spectra have been measured. Next week the commissioning will continue with the fine alignment of the PM/TM mirrors and the focusing of the beam onto the entrance slit of the monochromator
18/10/2011The commissioning with x-ray beam has started
14/10/2011The control cabin is fully installed and furnished
23/9/2011The HECTOR (High-field vECTOR-magnet) end-station for XMCD-XMLD has been installed and tested (some pictures are available here).
Status
Beamline under commissioning since the 18th of October 2011
The installation of the main optical components of the beamline has started on the 8th February 2010 and was completed by May 2010. The delivery of the KB refocusing system chamber occurred in December 2010. However, the mirrors were delivered only in July 2011. The end-station for dichroism has successfully been installed in September 2011. The scattering end-station is currently in its final design phase. In the second half of 2010 and the first half of 2011 the main part of the beamline infrastructure has been installed (water and compressed air piping from the main circuits to the components, and all cabling concerning the optical part of the beamline, i.e. excluding end-stations).
The beamline has seen its first photons on the 7th and the 9th of June 2011 (at a limited storage ring current of 5 mA). During the few hours of beam availability, we took several images of the undulator beam (at various gaps and phases) with the DiagOn and we could detect the beam reflected by PM and TM. The "real" commissioning with x-ray beam has started on the 18th October 2011.
Photos
Photos of the installation of the preliminary infrastructure (July-October 2009)
Photos of the installation of the main optical components (January-May 2010)
Photos of the installation of the main beamline infrastructure (Summer 2010-Summer 2011)
Photos of the installation of the KB system, BRFM and I0 monitor (December 2010)
Photos of the Factory Acceptance Test of the XMCD cryomagnet (July 2011)
Photos of the installation of the XMCD support and common end-station platform (July 2011)
Photos of the installation of the control hutch (July-August 2011)
Staff
Scientists: Alessandro Barla and Manuel Valvidares
Soft x-ray beamlines supervisor: Eric Pellegrin
Mechanical engineer: Roger Martín Fernández
Mechanical technician: ------------------
Electronics engineer: Julio Lidón Simón (shared with all other beamlines)
Controls engineer: Jairo Moldes Fuentes (shared with the Accelerators Division)
Beamline characteristics
| Photon energy range | 80 to >3000 eV |
| Calculated flux at the sample (at a resolving power of 5000) |
2x1013 photons/s @ 150 eV 8x1012 photons/s @ 700 eV 5x1012 photons/s @ 1500 eV 2x1012 photons/s @ 2000 eV 4x1010 photons/s @ 3000 eV 5x109 photons/s @ 4000 eV |
| Maximum resolving power |
15000 for 80 eV < E < 1500 eV 5000 for E > 1500 eV |
| Beam size at the sample | variable between a minimum of 100(H)x20(V) micron2 and >1x1 mm2 |
The beamline is optimized for highest photon flux and energy resolution in the range between 150 eV and 2000 eV. However, the monochromator and undulator allow us to reach a lowest energy of 80 eV in circular polarization, thus covering the Si L edges. Above 2000 eV, the optics of the beamline has a reduced performance as compared to typical hard x-ray beamlines, but the flux and energy resolution should be high enough to perform x-ray absorption experiments at important edges (L edges of all the 4d metals and the M edge of U) and non-resonant x-ray diffraction, to be used as a complement of resonant soft x-ray diffraction.
The HU71 undulator might be used as a wiggler for energies above the cut-off of the first harmonics (about 1000 eV), improving the flux in elliptical polarization especially for energies above 2000 eV.
Technical Description
Documentation
Other Useful Information for Experiments
- Standard sample holder for the High-field vECTOR magnet (under development)
- Transmission sample holder for the High-field vECTOR magnet (under development)
