"Where is the forefront of your disciplines?" was the
question with which Pat Dehmer, associate director of DOE's Office of Basic Energy
Sciences (BES), challenged the 325 scientists who had come for last week's "Workshop
on Scientific Directions at the Advanced Light Source." Meeting in eight separate
"working group" sessions, leaders from around the world in the use of
synchrotron radiation thrashed out answers to Dehmer's challenge, then determined how the
ALS could be used to advance those forefronts. The results, said Berkeley Lab director
Charles Shank, were "historic."
From March 23-25, workshop attendees grappled with issues in a wide range of
disciplines where the exceptional brightness and coherence of ALS x-rays and ultraviolet
light might play a critical role. The eight working group sessions were organized under
the headings of strongly correlated materials; nanostructures/ semiconductors;
environmental and Earth sciences; polymers and soft matter; biosciences; catalytic
material/surface sciences; magnetic materials; atomic, molecular, and optical
physics/chemical dynamics. In each case, the conclusion was that the ALS is the right
machine at the right time.
"This workshop began rather modestly but expanded in scope as the registration
grew," Dehmer said. "With the quality of the working group session reports, we
have also increased our expectations." She commended the working group session
reports as being impressive enough that they will be submitted to an appropriate
scientific journal for publication.
From the workshop's outset, Director Shank made it clear that the purpose of the
working group sessions was to make "the most compelling case possible" for the
ALS' scientific program. In his address to the opening plenary session, Shank charged the
groups to determine the "exciting scientific issues, the role of the ALS, and what
specific tools are needed." He also emphasized that without a compelling scientific
case, the ALS would not be able to "command the resources it needs."
The critical link between strong, cutting-edge science and budgetary support from
Washington was later reiterated by Iran Thomas, who heads BES' materials science division,
a primary source of ALS funding.
"Scientific proposals must be pushing the barriers, stretching the forefronts of
their fields or they aren't going to be funded," Thomas said.
At the end of the workshop, Shank expressed satisfaction with what the working group
sessions produced. "The embryonic reports we have collected here are the fruits for
the future."
The workshop was jointly sponsored by the Lab, BES, and the University of California's
Office of the President. It was put together in response to the "Birgeneau
Report," a DOE-sponsored review of the four national synchrotron radiation
facilities. The report placed the ALS fourth in funding priority and cited the facility
for shortcomings in its science programs, user relations, and institutional support.
Neville Smith, who heads the ALS scientific program, was recognized by both Dehmer and
Shank for his central role in organizing this workshop. "It's been a stressful time
here (following the Birgeneau report)," he said, "and the success of this
workshop has been a morale booster. As I went around the different working group sessions,
it was gratifying to see that so large a turnout of distinguished colleagues had come to
Berkeley to help us develop a stronger scientific program."
 ALS
scientific program head Neville Smith
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Following this workshop, Smith said that the ALS management, in close
consultation with the users' executive committee and the scientific advisory committee,
will "devise a roadmap for the orderly build-out of the ALS." The next measure
of success, he said, will be the extent to which the workshop's results "generate
compelling research proposals" for the ALS.
The plenary sessions that opened and closed the workshop were chaired by Yves Petroff,
director-general of the European Synchrotron Radiation Facility. In addition to his chair
duties, Petroff also addressed the session, sharing his own experiences as head of a third
generation light source that Shank praised as being a "model facility." Petroff
joined the chorus in stating that large, expensive research facilities such as third
generation synchrotron radiation sources must "push experimentation to its
limit." He also stressed that such facilities must have strong in-house research
programs as well as strong outside user programs with several "outstanding"
experiments in the mix. Costs can be kept down with sound long-range planning, he said,
and there should be a "good coupling" of the facility with "neighboring
universities and laboratories."
Petroff expressed surprise at the Birgeneau report's conclusions because it is
"too soon" to compare the ALS to older facilities such as the synchrotron
radiation source at Brookhaven National Laboratory. "The Brookhaven facility is
fabulous now, but it, too, had its problems when it was first started," he said.
This view was strongly seconded by Giorgio Margaritondo of Switzerland, who spoke on
behalf of the European Commission Round Table for Synchrotron Radiation.
"The United States absolutely needs the ALS," Margaritondo said. "The
scientific case for third generation light sources is clear and extremely strong for both
soft and hard x-rays, and for coherence and brightness in soft x-rays, the ALS is the
best."
Holding this type of a workshop to help plot the future scientific course of the ALS
received high marks from Akito Kakizaki, representing the Photon Factory at the University
of Tokyo. "The results of this workshop will have benefits for our upgrade of the
Photon Factory," he said, an upgrade that is currently being debated in Japan.
Following the reports out of the working group sessions, the workshop concluded with an
open forum in which ALS users had the opportunity to air their opinions directly with
Werner Myer-Ilse, of the Center for X-Ray Optics, who chairs the ALS users' executive
committee, and deputy lab director Pier Oddone, who is overseeing the Lab's response to
criticisms in the Birgeneau report.
"Many aspects of our relations with users were reported to be a problem,"
Oddone candidly told an audience that filled the Bldg. 50 Auditorium. "We are charged
with creating a world-class user program at the ALS. We have heard much talk at this
workshop about brightness being the measure of quality (for ALS' beams). Our goal is to
make our users shine."
In the enthusiastic exchanges that followed, the concerns raised included the
possibilities of the ALS helping to defray user expenses, particularly with regards to
travel and lodging, and an increase in technical support, including help with sample
preparations. There were also calls to improve the proposal submission process and the
allocation of beamline time and resources.
Oddone was joined by Shank in pledging that these issues would be taken under
advisement. Said Shank, "The ALS is a national user facility, and it is therefore
incumbent upon us to accommodate outsider users and balance between internal and external
scientific programs."
Dehmer may have best summed up the spirit of the workshop in her concluding remarks.
Noting that scientific surprises and technological revolutions can't be predicted, she
pointed out that the only forecast about synchrotron radiation that has come true has been
the increased use of such light. DOE, she said, shared a commitment with Berkeley Lab, to
make the ALS "the premier source of soft x-ray and extreme ultraviolet light in the
world."
The most important elements of the "Workshop on Scientific
Directions at the Advanced Light Source," which was held last week at Berkeley Lab,
were its eight working groups. Organized according to areas of research where the
potential use of soft x-ray and extreme ultraviolet radiation is strongest, each group met
separately at locations around the hill. Their mission was to identify the hottest issues
in their fields and how the ALS could best be used to make a valuable contribution.
While the conclusions of these individual working groups are still being finalized,
there are some overall highlights that can be reported. In the materials sciences, the
topics generating the most excitement were unconventional superconductivity; magnetism for
multi-electron extended systems; reduced dimensionality, including nanostructures, quantum
wells, and mesoscopic devices; composite fermions; and the link between electronic
structure and physical properties.
Many of the experiments being considered to study these topics could only be done at
the ALS. Reasons cited included existing unique capabilities for soft x-ray absorption,
emission, and scattering, and for magnetic circular and linear dichroism; plus potential
capabilities in high-resolution angle-resolved photoemission; optical conductivity; and
spin-polarized photoemission.
In the environmental and earth sciences, excitement centered around the "three
S's" -- speciation of contaminants; spatial inhomogeneity at all length scales;
sopping wet. With its unique capabilities for applying soft x-ray spectroscopy through the
water window to in-situ speciation studies of soils, clays, minerals, and bio-organisms,
the ALS received a strong endorsement here. There was even a call for the ALS to build-out
an entire sector for environmental and earth sciences research.
In the biosciences, the fields of protein crystallography, x-ray microscopy and
absorption spectroscopy received the most attention. For protein crystallography, the ALS
was praised for its Macromolecular Crystallography Facility. There were calls for a
superbend microcrystallography MAD (multiple-wavelength anomalous diffraction) beamline,
greater use of existing ALS bend magnets, and the use of the ALS to do "all the
proteins in a small bacterium" as part of an expanded effort in structural genomics.
For x-ray microscopy and absorption spectroscopy, the ALS was seen as having an important
potential role in medical studies that include breast cancer, disorders in human blood,
and even Mad Cow disease. There was also a discussion of the ALS' enormous potential for
diagnostic and functional imaging.
Enthusiasm was also high in areas involving catalytic materials, interfaces, chemical
dynamics, and atomic physics. A more detailed report on the workshop results will be
forthcoming in a future issue of Currents. The next Research Review will also feature a
story on the science that is being done now at the ALS by users from outside of Berkeley
Lab.
