HR: 0800h
AN: MR11A-0899    [Abstracts]
TI: Simultaneous Measurements of Sound Velocities and Density: Brillouin Scattering and Synchrotron X-Ray Measurements at GSECARS, Advanced Photon Source
AU: * Bass, J D
EM: jaybass@uiuc.edu
AF: University of Illinois Urbana-Champaign, Geology Dept 1301 W Green St., Urbana, IL 61801 United States
AU: Sinogeikin, S V
EM: sinogeik@uiuc.edu
AF: University of Illinois Urbana-Champaign, Geology Dept 1301 W Green St., Urbana, IL 61801 United States
AU: Shen, G
EM: shen@cars.uchicago.edu
AF: Consortium for Advanced Radiation Sources, University of Chicago, Chicago, IL 60637 United States
AU: Prakapenka, V
EM: prakapenka@cars.uchicago.edu
AF: Consortium for Advanced Radiation Sources, University of Chicago, Chicago, IL 60637 United States
AU: Lakshtanov, D L
EM: lakshtan@hercules.geology.uiuc.edu
AF: University of Illinois Urbana-Champaign, Geology Dept 1301 W Green St., Urbana, IL 61801 United States
AU: Rivers, M
EM: rivers@cars.uchicago.edu
AF: Consortium for Advanced Radiation Sources, University of Chicago, Chicago, IL 60637 United States
AB: Simultaneous measurements of density (by x-ray diffraction) and sound velocities (by Brillouin scattering) would allow the determination of an absolute pressure scale. The equation of state and velocities as a function of pressure could be determined without resort to a secondary pressure standard. The accurate determination of pressure is one of the outstanding technical challenges in experimental mineral physics today. As a mean of performing such measurements, a Brillouin spectrometer is being installed at the GSECARS Sector 13 of the Advanced Photon Source (APS). Brillouin scattering would allow velocity measurements to be made on transparent samples at high pressures and/or high temperatures while xray diffraction on the samples will yield the density. We describe here the design of the system and progress toward a commissioning of this unique facility. Important design characteristics for the system are: 1) that it be user-friendly. It should be possible for the general user to operate the system without being an expert. 2) Doing a Brillouin experiment on the beam line should require a minimum of set-up time. In order to achieve these characteristics, we have adopted a novel optical design that allows the Brillouin optics into place easily and should not require frequent alignment of the sensitive spectrometer optics. In addition, all adjustments of the optics that are normally performed during a Brillouin experiment can be performed from outside the hutch. We describe in this presentation the detailed design characteristics of this facility.
DE: 3924 High-pressure behavior
DE: 3954 X ray, neutron, and electron spectroscopy and diffraction
DE: 3994 Instruments and techniques
DE: 3309 Climatology (1620)
DE: 3319 General circulation
SC: Mineral and Rock Physics [MR]
MN: 2004 AGU Fall Meeting