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Last Updated: | 24 JUNE 2002 |
| Content Owner: | L. Dunn | |
| Page Editor: | L. Dunn |
**** **** **** * * * * * * **** **** **** * * * * * * **** **** * * **** HEADLINES - a digital monthly publication
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Contents of This Issue:
1. A Perspective from the SSRL Director
(contact K. Hodgson, hodgson@ssrl.slac.stanford.edu
)
It is an exciting and challenging time for SSRL and I would like to share my perspective of some of the developments that will dramatically change what we provide to our user community in the coming years. For the immediate future, the SPEAR3 accelerator upgrade project remains on schedule and within budget for a planned 6-month installation period beginning in April, 2003. Following commissioning, SPEAR3 will provide high brightness beams for our users in 2004 and beyond. We are also making significant progress on the beam line upgrade program and expect that most of the wiggler and undulator stations will be able to make full use of the new source shortly after it is commissioned. We are working closely with the SSRL Users' Organization Executive Committee to disseminate information on the SPEAR3 project, optimize the beam line upgrade in the transition period and find the best ways to help our users during the shutdown. In close cooperation with our colleagues at SLAC, ANL, LLNL, UCLA and other institutions, we have made very significant progress on the x-ray FEL project (LCLS), which will produce ultra-bright, ultra-short coherent x-rays. The first DOE "Lehman Review" in April of the technical, manpower, schedule and cost of the project went very well and provided the mandate to transition from the R&D phase into the project engineering and design phase (PED) in FY2003. On the current schedule, we expect to be able to build the LCLS and deliver its remarkable beams by around 2008. In the meanwhile, we will be using mainly existing components to develop a short pulse x-ray source experiment (SPPS) where, in FY2003, we will create 80 fsec bursts of x-rays with reasonably high numbers of photons per pulse (but not as great as the LCLS itself!) to begin to explore areas of ultrafast x-ray science and develop approaches that will be very important for early effective utilization of the LCLS. While building for the future, we must also continue to effectively operate SPEAR in its current mode and continue to best serve our user community. A recent DOE Inspector General audit found that SSRL makes very effective use of its beam time in serving the users through its integrated, general user approach. All of this effort, success and progress is possible only with a dedicated and talented staff, faculty and advisory committees to whom I extend the greatest thanks. Without the full support of DOE none of this would be possible. We continue to welcome suggestions and feedback, especially how we can better serve the needs of our users and promote exciting science. Nevertheless, the coming years will be a very challenging time of transition for SSRL and we appreciate the continued understanding, patience and cooperation of our users as we build new sources for tomorrow's science.
2. Science Highlight - SSRL Studies Aid
Environmental Cleanup at Rocky Flats
(contact: David L. Clark, dlclark@anl.gov)
Without dispute, decades of nuclear weapons testing have left behind trace plutonium in the soils of Rocky Flats, Colorado. After being designated as a Superfund cleanup site by the Environmental Protection Agency, a massive cleanup effort was launched in 1995. The question that researchers at Los Alamos National Laboratory have been charged with answering is the chemical speciation (i.e. physical form, local/molecular structure and composition, oxidation state, host-phase identity) and spatial distribution of the trace Pu contamination. In general, insoluble phases pose less risk to humans, wildlife, and water supplies because the rate of metal ion release is slow, sometimes nonexistent. Readily leachable phases pose the greatest short-term threat to environmental health. Using XAS methods at SSRL's new actinide facility at Beam Line 11-2, Dr. Steven Conradson and other co-workers at LANL have determined that the main species of Pu in the contaminated soils at Rocky Flats is PuO2, a relatively insoluble form of Pu(IV). This Pu was found to be localized in the upper 12 cm of soil, with hotspots present in various locations. It is thought to represent a potential public health hazard because of the tendency of Pu in this form to hydrolyze, become electrically charged, and bind to the surfaces of colloidal particles, which can be transported in groundwater and surface waters. Confirmation that only the upper level of the soil at Rocky Flats is contaminated has played a key role in determining appropriate remediation strategies while saving tax payers many dollars in the process.
More information regarding this research can be found at:
http://www-ssrl.slac.stanford.edu/research/highlights_archive/rockyflats.html
3. SLAC Science Policy Committee Meets
(contact: K. Hodgson, hodgson@ssrl.slac.stanford.edu
)
The SLAC Science Policy Committee (SPC) held its spring meeting on May 3-4, 2002. The SPC is SLAC's highest level external advisory committee, reporting to Stanford University President John Hennessy on all aspects of ongoing activities, future plans, ES&H, etc. The SSRL-related portion of the SPC meeting featured an overview by SSRL Director Keith Hodgson and a full report on the LCLS Lehman Review by Project Director John Galayda. A talk on the spectacular research on RNA Polymerase was given by Professor Roger Kornberg, Department of Structural Biology, Stanford University, and the SSRL Users' Organization Executive Committee (SSRLUO-EC) gave its annual report on the users' perspective of SSRL operations and future plans (Corwin Booth, Chairperson). At its closeout, the SPC was very positive about the SSRL plans for the future - including SPEAR3, LCLS and the SPPS experiment. They urged a careful look at the schedule for SPEAR3 installation and felt that the length of the shutdown should not be extended. The SPC was also pleased to hear of the plan to reformulate the LCLS SAC into a group that would review and recommend the specific experiments to be run on LCLS, drawn from a broad call to the community. Terms for several of the SPC members with experience in synchrotron radiation will be concluding in 2002 and suggestions for nominations are very welcome (contact K. Hodgson at the email above).
4. SSRL Faculty News
(contact: Gordon Brown Jr, Chair, SSRL Faculty,
gordon@pangea.stanford.edu)
I am very pleased to report that Dr. Britt Hedman has been appointed Professor (Research) in the SSRL Division of the SLAC Faculty, effective May 1, 2002. This faculty appointment is long overdue and recognizes Britt's major research contributions. Dr. Hedman has pioneered the development of soft X-ray absorption spectroscopy as a modern tool for probing ligand-metal interactions in complex metalloproteins and metalloenzymes. Her XAS studies in this area, in collaboration with Profs. Keith Hodgson and Edward Solomon (Stanford University), have led to the development of the methodology for S K-edge spectroscopy as well as important discoveries about metal-sulfur bonding in metalloproteins. She is also widely acknowledged as one of the main drivers in applications of multiple scattering methods for the analysis of XAS data in collaboration with Prof. John Rehr (University of Washington) and Prof. Rino Natoli (Laboratori Nazionali di Frascati, Frascati, Italy). The SSRL Faculty welcomes Britt and anticipates many more contributions from her in the future.
It is also a pleasure to announce the appointment of Prof. George Sawatzky (Professor of Physics at the University of British Columbia) as a Consulting Professor on the SSRL Faculty. George's appointment brings expertise to the SSRL faculty in condensed matter physics of highly correlated materials.
Finally, I am happy to report that Affiliated SSRL Faculty Member Dr. Vijay Pande (Chemistry Department, Stanford University) has been recently recognized by the Massachusetts Institute of Technology as one of the top 100 young (under 35) Technology Review innovators because of his distributed-computing approach to protein folding. Vijay wrote an algorithm that enables thousands of isolated personal computers to calculate portions of a folding sequence and then combines their solutions. His algorithm has been downloaded by about 75,000 volunteers whose PC's carry out folding sequence calculations during their normal idle time. As the MIT Technology Review citation states, "On any given day, 35,000 PC's are providing computing power" to Vijay's project. (http://www.technologyreview.com/articles/tr100_0602.asp)
5. Want to Learn About SR Applications in the
Physical Sciences?
(contact: Anders Nilsson, nilsson@slac.stanford.edu)
There's still room for about 10 more participants in the 2002 Stanford- Berkeley summer school physical sciences SR course. This year the summer school will be held at Stanford University from July 7-13. The program will provide a comprehensive overview of the synchrotron radiation process, requisite technologies and a broad range of scientific applications. It will cover both fundamentals of EUV, soft x-ray, hard x-ray synchrotron radiation and its use in spectroscopy and diffraction. Science applications will be given both in physics, chemistry and material science. Lectures will be presented by scientists from the sponsoring organizations and affiliated user communities. The attendees will participate in experiments on different beam lines at the Advanced Light Source (ALS) and make visits inside the storage ring at the Stanford Synchrotron Radiation Laboratory (SSRL). For more information and how to apply see the Physical Science School web page.
6. SSRL Users' Organization Executive Committee
Update
(contact: Corwin Booth, chbooth@lbl.gov)
Representatives from the users organizations of each of the four DOE synchrotron light sources met in Washington DC on April 17-18. SSRL users were represented by the SSRLUO-EC Chair and Vice-chair, Corwin Booth and Uwe Bergmann, respectively. On the 17th, the group met with staff from the House and Senate Energy and Water Appropriations Committees, the Office of Management and Budget, the Office of Science and Technology Policy, and the House Science Committee's Energy Subcommittee. On the 18th, Booth and Bergmann met with staffers for Representatives Ellen Tauscher (D-CA 10th) and Barbara Lee (D-CA 9th) and California Senators Dianne Feinstein and Barbara Boxer. Booth and Bergmann also met with Representative Zoe Lofgren (D-CA 16th) whose district includes parts of Silicon Valley. Although these meetings were effective in creating and maintaining awareness about synchrotron science, the SSRLUO-EC feels that the entire user community should participate in this activity and encourages users to contact their respective representatives. Corwin Booth has put together a web page to aid and encourage activism on the part of the SSRL user community by providing links to congressional committees, etc. (http://moseley.ucsc.edu/ssrluo/). Additionally, Jane DeWitt of the SSRLUO-EC has volunteered to coordinate this effort, and she may be contacted if users would like more information (dewitt@sfsu.edu).
On May 9th, the SSRLUO-EC held an open session meeting for all interested users.
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SSRLUO- EC meeting minutes are posted on the web.
7. Co-Chair of PCAST Visits SLAC
Floyd Kvamme, Co-Chair of the President's Council of Advisors on Science and Technology (PCAST) visited SLAC for the first time on Wednesday, May 22. Kvamme's visit included a tour of the SSRL experimental floor with specific emphasis on scientific and technological advances enabled by synchrotron radiation, including examples in the computer and biotechnology sectors.
PCAST was established in 1990 by President George Bush (the elder) to provide a conduit for advice from the academic community and private sector on technology, scientific research priorities, math and science education. The council was reinstituted under the current Bush administration by Executive Order in September 2001. PCAST currently consists of 23 members plus the Director of the Office of Science and Technology Policy, John Marburger, who serves as co-chair with Kvamme. Kvamme's most recent industrial connection is with Kleiner, Perkins, Caufield and Byers, a partnership supporting entrepenurial ventures - coincidentally located across the street from SLAC. Kvamme also serves on several boards including Photon Dynamics, Power Integrations, Triquint Semiconductor, Harmonic Lightwaves, Prism Solutions, Brio and Gemfire.
8. Addressing SPEAR Accelerator Performance
Issues
(contact: Heinz-Dieter Nuhn, nuhn@ssrl.slac.stanford.edu)
Have you ever wondered why SSRL user operations appear to be interrupted every two weeks or so by a 48-hour period marked as MA or AP on the SPEAR Operating Schedule? These "mystery" blocks of time are being put to good use for SPEAR Maintenance (MA) and Accelerator Physics (AP) periods. SPEAR Maintenance generally takes place during a 12-hour period once per month to inspect and/or repair accelerator components. The work is carried out inside the SPEAR tunnel as well as in the equipment shelters while the accelerator is down. During AP periods, the accelerator is normally up and operating and physicists are running experiments to conduct various physics studies. During the current run the focus of these activities has been on preparation for the SPEAR3 upgrade, electron beam dynamics studies and accelerator performance studies aimed at the preservation and improvement of photon beam stability, electron beam lifetime and reducing injection time. Over the years these studies have directly resulted in developments that have improved the performance of the SPEAR light source.
Due to manpower requirements needed for the SPEAR3 upgrade preparations, the Accelerator Physics program presently runs at a reduced pace. This is why beam time originally set aside for accelerator physics on the schedule has been turned back over for user operations several times during this run. For the same reason only one AP period will be scheduled per month during the FY2003 experimental run. Accelerator Physics schedules are posted about one week before the corresponding period.
Recently, problems with the SPEAR RF system have resulted in intermittent beam instabilities and beam dumps. The accelerator group has been working on understanding the problem and has been receiving excellent support from the SLAC Klystron Department in diagnosing and correcting the problem. The spare klystron has been installed at the klystron test laboratory, and processing is going well. High voltage and RF power tests will be done. If all goes as planned the klystron will be installed in SPEAR during the next scheduled maintenance period on June 3. In the meantime the maximum electron beam current in SPEAR has been reduced to minimize the amplitude of the instabilities and avoid beam dumps as much as possible. Updated information is available on the SPEAR status line at 650-926-2326 and also via the web at: http://www-ssrl.slac.stanford.edu/talk_display.html
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10. Upcoming Events at SSRL and Elsewhere
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11. User Research Administration
Announcements
(contacts: Cathy Knotts,
knotts@ssrl.slac.stanford.e du
,
Lisa Dunn, lisa@ssrl.slac.stanford.edu)
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SSRL Headlines is published electronically monthly to inform SSRL users, sponsors and other interested people about happenings at SSRL. SSRL is a national synchrotron user facility operated by Stanford University for the U.S. Department of Energy Office of Basic Energy Sciences. Additional support for the structural biology program is provided by the DOE Office of Biological and Environmental Research, the NIH National Center for Research Resources and the NIH Institute for General Medical S ciences. Additional information about SSRL and its operation and schedules is available from the SSRL WWW site: http://www-ssrl.slac.stanford.edu/
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