Australian Synchrotron Research Program, July 1999
Advanced Photon Source, Chicago, USA
In a previous article Drs Garry Foran and James Hester described how the Australian National Beamline Facility (ANBF) evolved into the Australian Synchrotron Research Program (ASRP). The authors gave a detailed account of the original facility at the Photon Factory, which has yielded so much excellent science and continues to go from strength to strength.
The expansion of the ASRP into the Advanced Radiation Source (APS) in Chicago now gives Australian researchers access to third generation synchrotron radiation (SR). Highly collimated and intense light from the APS will open up such areas as time-dependent studies of crystalline and amorphous condensed matter systems, as well as allowing us to use traditional X-ray scattering techniques on micron-sized sample regions. In addition, the X-ray energies generated by APS insertion devices and bending magnets extend the SR energy ranges normally available at second generation sources to well above 100keV (less than 0.124Å in wavelength). This will open the way to scattering studies of high-Z materials for which X-ray absorption at more "conventional" energies is a serious problem.
The Australian involvement in a number of Collaborative Access Teams (CATs) at APS is first and foremost a science-driven enterprise, designed to complement our existing facility at the ANBF in Japan. This is reflected in the choice of beamline sectors to which the ASRP contributes funding and manpower. Our support of these sectors has guaranteed us substantial beam time, a sizable influence on the scientific directions taken by these facilities and a point of ingress for Australian scientists into the larger APS community.
Collaborative Access Teams at the APS
Each CAT "owns" at least one sector on the APS storage ring. Each sector contains two primary radiation sources; a bending magnet and an insertion device (usually an undulator). An undulator beamline will typically accommodate experiments where highly intense and well-collimated beams with small spatial dimensions (1mm down to 1m m) are required. Bending magnet beam lines, on the other hand, are more suited to applications where larger beam footprints are required (as is often the case for imaging) or in applications such as multiple-wavelength anomalous diffraction (MAD) where a smooth energy spectrum profile is advantageous.
The instrumentation and beamline facilities available at the APS are far too numerous to document here in detail, although a brief outline of each of the sectors directly involving the ASRP will be given. We would like to encourage interested researchers to visit the following web sites for more information:
·www.ansto.gov.au/natfac/asrp.html - for an overview of the ASRP, how to apply for beamtime, e-mail contacts and links to relevant web sites.
·www.aps.anl.gov - for an overview of the Advance Photon Source in Chicago and links to all its CATs.
·cars1.uchicago.edu/chemmat/chemhome.html - for an overview and details of the ChemMatCARS CAT (sector 15).
·cars1.uchicago.edu/biocars/biocars_home_page.html – for an overview and details of the BioCARS CAT (sector 14).
·www.aps.anl.gov/sricat/ - for an overview and details of the SRI-CAT (sectors 1 – 4).
This sector is devoted to the study of chemistry and materials science. The insertion device beamline (15-ID) is currently under construction and well on the way to completion, with a bending magnet beamline (15-BM) planned within the next few years.
This facility is run by the University of Chicago and includes a number of other universities and institutes in its consortium. Initially, this CAT will service four distinct areas:
·Single crystal crystallography
·High energy resolutions XAFS
·Static and time-dependent reflectometry on liquid and solid surfaces
·Static and time-dependent small and wide angle X-ray scattering (SAXS /WAXS) on liquids and ‘soft’ solids such as polymers and fibers.
Dr David Cookson is the ASRP scientist stationed at this sector. He previously worked with Dr Garry Foran at the ANBF in Japan for five years before relocating to Chicago.
Also run by the University of Chicago, this CAT is devoted to protein and virus crystallography. It has been fully constructed and is now accepting Australian users. It has three separate beam lines:
1) Insertion beamline 14-ID-B, is designed for both high-resolution monochromatic crystallography (including MAD), and for time resolved studies using pink beam (ie white beam with higher energies removed) in Laue configuration.
2) Bending magnet beamline 14-BM-C, designed for monochromatic protein and virus crystallography. This is the "work horse" beamline optimized for more "routine" protein diffraction experiments.
3) Bending magnet beamline 14-BM-D, designed for MAD, monochromatic and Laue experiments. >
Dr Harry Tong is the ASRP scientist stationed at this sector. Harry joined the ASRP one year ago, having had a number of years of protein crystallography experience working in Australia, Canada and the Netherlands.
SRI-CAT(Sectors 1 to 4)
The Synchrotron Radiation Instrumentation CAT is run by the APS itself under the Experimental Facilities Division (XFD). This CAT was formed with dual missions: to perform basic research in synchrotron-based optics and techniques, and to develop and operate strategic instrumentation that takes full advantage of the capabilities of the APS. As was originally envisioned, new CATs building their own facilities at the APS have used much of the technology arising from SRI-CAT research, especially in the area of high-heat load optics.
About 80 XFD staff members are directly involved with beam-line operations. Three of the four sectors run by the CAT are currently operational with the fourth scheduled to take first light next year. A summary of the sectors and their associated beam lines follows:
Sector 1: Time resolved studies, high-energy X-ray studies and high heat load studies.
This sector has presently one undulator line and one bending magnet line. It has flexible beam lines, which would be suitable for Australian users wishing to use third-generation radiation in an ad hoc setup.
·1-ID (undulator line): Energy range from 5-130 keV. Scattering from disordered materials, X-ray diffraction, high-energy microprobe studies (40-60 keV).
·1-BM (bending magnet): Time resolved spectroscopy, energy dispersive XANES, dispersive diffraction.
Sector 2: X-ray microprobe (including micro-tomography, fluorescence and diffraction), high-resolution soft X-ray spectroscopy and deep X-ray lithography.
This sector has one bending magnet line, and four branched undulator lines, two taking radiation from a soft X-ray undulator and two using a hard X-ray undulator.
·2-ID-B (soft X-ray undulator): high-resolution micro imaging (tomography, fluorescence, diffraction etc), coherent scattering and interferometry.
·2-ID-C (soft X-ray undulator): high-resolution soft X-ray spectroscopy. Spectromicroscopy and diffraction of surfaces and near surface regions. Magnetic studies.
·2-ID-D and 2-ID-E (hard X-ray undulator): high resolution micro-fluorescence imaging , micro-diffraction and coherence based techniques.
·2-BM (bending magnet): micro-tomography, diffraction, fluorescence microprobe, high-resolution fluorescence spectroscopy, deep X-ray lithography for prototyping micromachined parts.
Sector 3: Inelastic X-ray and nuclear resonant scattering studies.
3-ID (undulator): High energy-resolution X-ray scattering in the 6-30 keV range.
Sector 4: Polarization/magnetic studies.
This sector is being built and will become operational next year. The sector will comprise a soft and hard X-ray undulator line both delivering circularly polarized light and both being able to operate in parallel. Present magnetic/polarization studies are pursued mainly in sectors 1 and 2.
Dr Anton Stampfl is the ASRP scientist stationed at these sectors. Prior to this position, Anton worked in Germany at the Fritz Haber Institut and Freie Universität in Berlin and at La Trobe University in Melbourne.
[About the SCANZ | SCANZ Executive | What's New | Contact Information]
[Membership | SCANZ Conferences and Events | Charter | Educational Material]
[SCANZ Related Websites | Other Web Sites]