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Last Updated: | 16 AUG 2001 |
| Content Owner: | L. Dunn | |
| Page Editor: | L. Dunn |
**** **** **** * * * * * * **** **** **** * * * * * * **** **** * * **** HEADLINES - a digital monthly publication
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1. Science Highlight - Complex Materials Research by Angle-Resolved Photoemission
Spectroscopy:
Challenging the Mystery of the High Tc Superconductivity
(contact: DongHui Lu, dhlu@stanford.edu)
Extensive research efforts to study the novel electronic properties of high-Tc superconductors and their related materials by angle- resolved photoemission spectroscopy at a recently commissioned Beam Line 5-4 (led by Z.-X. Shen) continue to be successful, producing many important results. These results, which are highlighted by five articles recently published in Physical Review Letters and one in Science, brought our understanding steps closer to solving the mystery of the high-Tc superconductivity.
More information regarding this research can be found at:
http://www-ssrl.slac.stanford.edu/research/highlights_archive/high-tc.html
Several members of the Shen group who contributed to the research
referenced above, including Changyoung Kim, N. Peter Armitage, Filip
Ronning and Donglai Feng are leaving Stanford to take new positions.
We wish them well in their future endeavors!
2. 2000-2001 Experimental Run Highlights
(contact: Ed Guerra, guerra@slac.stanford.edu)
In a continuing trend, SSRL has just completed another very successful experimental run cycle with SPEAR delivering an average of 94.9% of the beam scheduled to users. The beam was remarkably stable from the start, due in part to extensive maintenance performed on the actuator and RF systems last summer. The injector worked well with turn-around times on the order of 20 minutes. An additional 20% improvement in the lifetime was achieved during the last two months of the run when a new fill pattern using less current per bunch was implemented.
In February the BL10 wiggler developed a problem causing a catastrophic vacuum failure. Under circumstances that could easily have led to a lengthy downtime across all beam lines, staff responded promptly and effectively to remove the wiggler and get SPEAR operating in just 4 days. (See update on I.D. repair below.) To help offset the beam time loss to users, the following accelerator physics period was converted to user operations time and the recertification of the Personnel Protection System in April, normally a 3-day process, was safely completed within just one shift. While BL10 users necessarily did not fare as well, every effort was made to accommodate their beam time requests on other beam lines during the final scheduling period.
Additional unscheduled downtime, due to the power crisis in California, was successfully averted. When asked to cut back on site-wide power consumption several times over the past few months, SLAC management was able to reduce power consumption in other areas rather than to take SPEAR off-line.
At the end of the run, 3 GeV tests of the injector were conducted
successfully for SPEAR3 at-energy injection. 3 GeV beam was established
through the booster-to-SPEAR transfer system with the RF frequency at the
new SPEAR3 design value.
3. Stanford-Berkeley 2001 SR Summer School: A Successful Start
to the
First in a Series
(contact: Anders Nilsson, nilsson@slac.stanford.edu)
The first Stanford-Berkeley summer school on synchrotron radiation and its applications was held July 8-14. The program was designed to introduce prospective users to the fundamental properties of synchrotron radiation and the understanding and use of several SR techniques including spectroscopy, scattering and microscopy in various scientific applications. Selected on the basis of their academic record and written description of how the use of SR could impact their planned research projects, the 36 students (representing 14 different nationalities) came from a diverse range of scientific fields including atomic and molecular physics, condensed matter physics, surface science, polymer chemistry, environmental science and biophysics.
The school was held at UC Berkeley and was sponsored by SSRL, ALS, LBNL and the UCB Division of Continuing Education in Engineering. The program was coordinated by Anders Nilsson at SSRL and David Attwood at LBNL. Lectures were given by David Attwood (LBNL), Anders Nilsson, Jo Stöhr and Sean Brennan (SSRL), Eli Rotenberg (ALS), Steve Kevan (Univ. of Oregon), Gordon Brown (Stanford Univ.) and Harald Ade (North Carolina State Univ.). The program also included afternoon visits to both SSRL and ALS, giving the students opportunities to interact with the professional staff and graduate students at both facilities. These visits included lectures on storage rings, beam line design and the free electron laser project, capped off by tours of the experimental facilities. The closing session featured a stimulating discussion between the students and lecturers. Students were encouraged to ask questions rarely addressed in such a forum, e.g. - "What is important for my future career?" and "How do I design a good experiment?"
It was rewarding to see all the positive interactions between the
lecturers and the students - and among the students themselves. They
learned a lot from each other and generated friendships that may last
for a long time. Next year the joint school is planned to take place at
Stanford. We hope that this will become an annual event in the future.
4. SSRL Well Represented at the American Crystallographic
Association
Meeting
(contact: Peter Kuhn, pkuhn@stanford.edu)
SSRL was well represented at this year's meeting of the American
Crystallographic Association in Los Angeles during the week of July 22nd.
Beyond numerous oral and poster presentations by the user community,
which referenced SSRL as a research resource for their scientific
program, a number of SSRL staff were directly involved with the
scientific program of the conference. Staff scientists Michael Soltis and
Ana Gonzalez chaired the sessions on New Computational and Experimental
Methods, and Applications of Synchrotron Radiation to X-ray Diffraction,
respectively. Staff scientists Jessica Chiu, Ashley Deacon and Peter Kuhn
presented results on the development of Collaboratory for
Crystallography, the Automated Structure Analysis of Proteins, and the
Joint Center for Structural Genomics, respectively. The meeting was well
attended by over 900 scientists with a strong focus on topics of
crystallographic methods and novel approaches. A full day symposium was
dedicated to advances in high-throughput structural biology with emphasis
on the emerging field of structural genomics.
5. The Shutdown Clock is Ticking
(contact: Piero Pianetta, pianetta@slac.stanford.edu)
As has been the case over the past several years, preparations for SPEAR3 have resulted in shutdowns that seem as busy as the run itself. Shutdown activities began July 5 and the rush is on to get the work done before start-up activities begin on September 24. The West Pit area is seeing extensive shielding modifications that include completion of the concrete roof shielding, filling of the remaining "moat" in the pit itself, and addition of a bending magnet alcove between BL11 and the West Pit. Once this is complete, work will begin on a new beam line enclosure that will continue Building 131 all the way to the SPEAR injection line. A 6500 sq. ft. ground floor will be built initially with the second floor left unfinished. Over the next few years the second floor will be completed to provide needed laboratory, user and staff space as SPEAR3 comes on line.
On the beam lines themselves, much of the work has been split between repair/maintenance, SPEAR3 upgrades and new facilities. Beyond the usual shutdown calibration and cleanup work, the repair/maintenance activities include replacement of the BL6 and BL10 M0 mirrors, repair of the BL7 separation flange vacuum leak, repair of the BL6 beam position monitor leak, and M0 mirror repairs/adjustments on beam lines 9-2, 9-3, 11-1 and 11-2.
With ongoing preparations for the upgrade of all the beam lines to handle
the higher powers provided by SPEAR3, the activity level on the SPEAR3
Beam Line Upgrade project has been very high throughout the year. This
shutdown sees the construction of several liquid nitrogen cooled
monochromators that will allow the beam lines to run at higher energies
and at full flux under SPEAR2 (and SPEAR3). The LN2 mono will be
installed on BL9-3 this summer and two more will be installed on BLs 6-2
and 10-2 by the end of the first quarter in calendar year 2002. This
represents one of the first SPEAR3 upgrades of an existing beam line.
Another noteworthy milestone is the completion of the specification for a
spherical grating monochromator that will replace the existing Locust
monochromator on BL5. This monochromator will cover the carbon K through
transition metal L edges (250 - 1200 eV) with high resolution and
throughput while the existing normal incidence monochromator (NIM) will
continue to serve the correlated materials community in the low photon
energy range. Finally, work is continuing on BL11-3 with the goal of
installation early in 2002. This beam line will provide a 10 keV focused
beam for thin film diffraction and macromolecular crystallography.
6. BL10 Insertion Device Repair on Track for November User
Operations
(contact: Ann Trautwein, atraut@slac.stanford.edu)
The SSRL Mechanical Services Group has been working hard to ensure that
the BL10 insertion device repair remains on schedule. The two damaged
magnet keepers have been removed from the girder and replaced with
spares.
The lower girder is now repaired and once again installed and aligned on
the
girder. The magnet is currently undergoing magnetic measurement and
should be
ready for the vacuum chamber by the end of the week. In a concurrent
effort, machining on the vacuum chamber has been completed with the last
piece (the splice) currently being electropolished. Welding on the
vacuum
chamber should be completed this week. The chamber will then be leak
checked,
measured and baked. Installation into the magnet will commence on August
13th
and the line should be available for user operations early in the next
run.
7. Semi-annual SPEAR3 Lehman Review
(contact: Tom Elioff, telioff@slac.stanford.edu)
The semi-annual DOE Lehman review of the SPEAR3 Project was conducted
on July 24, 2001. The project team described accomplishments to date
together with future schedules for all of the major technical systems of
this new 500 mA electron storage ring. The review committee concluded
that the project remains on track for schedule, costs and meeting
technical scope objectives. No issues were raised; however, the
committee recommended that the project continue to refine the six-month
final installation plan scheduled for the end of FY03 together with
associated costs and contingencies.
8. SSRL's 28th Annual Users' Meeting is Coming Soon!
(contact: Cathy Knotts, knotts@ssrl.slac.stanford.edu)
Abstracts for 28th Annual SSRL Users' Meeting Due August 24th - Users,
including students and postdocs, are invited to submit abstracts for
posters and oral presentations at SSRL's Annual Users' Meeting on October
17-19, 2001. The poster session and reception will be held on Thursday,
October 18th and will include the student poster competition, with prizes
to be awarded at the dinner later that evening. Oral presentations will
be selected from the abstracts received for inclusion in the program.
Interested users should submit a one-page abstract detailing research
done at SSRL over the past year. Abstracts can be submitted
electronically at:
http://www-ssrl.slac.stanford.edu/conferences/ssrl28/abstracts.html
Nominations for 4th Annual Farrel W. Lytle Award Due September 5th - The
Lytle Award was established by the SSRL Users' Organization Executive
Committee (SSRLUO-EC) to promote important technical or scientific
accomplishments in SR-based science and to foster collaboration and
efficient use of beam time among users and staff at SSRL. The names of
the award winners are displayed on a plaque in the User Research
Administration lobby and each recipient receives $1,000. All SSRL users
and staff are eligible for this award. All nominations will be reviewed
and the recipient selected by members of the SSRLUO-EC. The Award will be
presented at the Users' Meeting Dinner. More information regarding the
nomination process can be found at:
http://www-ssrl.slac.stanford.edu/conferences/ssrl28/lytle.html
Nominations to Fill Vacancies on SSRLUO-EC Due September 18th - We are
currently soliciting nominations for five general positions in the
following disciplines: materials/chemistry (2), environmental/geosciences
(1), macromolecular crystallography (1), and structural molecular biology
(1). In addition, we seek nominations for a graduate student member of
the committee. Members will be elected by the SSRL user community and
will serve a two-year term, with the exception of the person elected
Chair who serves a three-year term. All newly elected members begin their
term following the Users' Meeting. Nominations should be sent via email
or regular mail to Cathy Knotts and should include nominee's name,
institution, primary area of discipline, and whether or not they have
agreed to have their name appear on the ballot. See:
http://www-ssrl.slac.stanford.edu/conferences/ssrl28/ballot.html
Program and registration information for the Users' Meeting will
be posted to the meeting website soon at:
http://www-ssrl.slac.stanford.edu/conferences/ssrl28/
9. User Research Administration Announcements
(contacts: Cathy Knotts, knotts@slac.stanford.edu,
Lisa Dunn, lisa@ssrl.slac.stanford.edu)
X-Ray/VUV Beam Time Requests - Due by August 3rd - Beam time requests
have been mailed to spokespersons with active X-ray/VUV proposals. These
need to be completed and returned to SSRL by August 3rd in order to be
scheduled during the first scheduling period, November 1, 2001 through
January 30, 2002. The beam time request forms can be also submitted
electronically through our website at:
http://www-ssrl.slac.stanford.edu/users/user_admin/xray_btrf.html or
http://www-ssrl.slac.stanford.edu/users/user_admin/vuv_btrf.html
Macromolecular Crystallography Beam Time Requests - Spokespersons will
receive an email message in August regarding beam time requests for the
November 2001 through February 2002 period. Users can submit their
requests early if desired by using the following web form:
http://smb.slac.stanford.edu/admin/form_bio_btrf.html
10. SSRL Job Opportunities
(contact: Rochelle Roberts, rroberts@slac.stanford.edu)
SSRL currently has positions available for mechanical, electronic and
beam line engineers, technicians and administrative staff. More
information is available at the following web site:
http://www-ssrl.slac.stanford.edu/jobs.html
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 Sciences. Additional information about SSRL and its operation and schedules is available from the SSRL WWW site: http://www-ssrl.slac.stanford.edu/
You can subscribe or remove your name from the distribution list by sending a brief email with your request to Lisa Dunn, editor, at lisa@ssrl.slac.stanford.edu.