The materials science and powder diffraction beamline at ALBA
|Michael Knapp , Inma Peral , Salvador Ferrer|
CELLS (ALBA), Campus UAB, Barcelona 08193, Spain
We will present the design concept, and current status of the new Materials Science and Powder Diffraction beamline at ALBA. After the conceptual design report of the end-stations was presented to the user community in late 2007, it was decided that the beamline would be devoted mainly to two types of diffraction experiment: high resolution powder diffraction and high pressure diffraction using diamond anvil cells. Single crystal diffraction experiments will be possible but in a second phase of the beamline.
The beamline will operate between 8 to 50 keV. This energy range covers very well the desirable range for almost any powder diffraction experiment, and at the same time it will be possible to perform both total scattering experiments, and high pressure diffraction; for which it is desirable and sometimes necessary to have high energy sources (E > 30 keV). To accommodate the different experimental techniques there will be two experimental end stations, one devoted to powder diffraction and the second one to high pressure experiments. A third end-station is planned for a second phase, this end-station will be devoted to single crystal experiments. For this station it has been decided to install an independent and compact set-up that is commercially available and that would not compromise the rest of the layout of the beamline.
The optical elements have been recently awarded, thus the optics layout will be presented as well as the expected beam performance. The optics for the powder diffraction station includes a collimating mirror and a “double crystal” Bragg-monochromator. The energy resolution for this kind of monochromators is typically ΔE/E=2·10-4 depending mainly on the choice of crystals. The high-pressure experiments need a beam diameter below 100µm. Therefore, a KB-mirror system will be installed behind the standard Bragg monochromator.
The end-stations layouts that have been agreed with the user community will be presented. The procurement of the different parts is now in progress; we will present the current status of the design, procurement and installation of the experimental stations.
Presentation: Poster at 11th European Powder Diffraction Conference, Poster session, by Michael Knapp
See On-line Journal of 11th European Powder Diffraction Conference
Submitted: 2008-04-30 16:03 Revised: 2009-06-07 00:48