1. QUANTUM CHAOS IN HELIUM
by Annette Greiner
(Contact: Kaindl@physik.fu-berlin.de)

Two's a party, three's a crowd--especially in a tiny space. Two objects that exert electrostatic or gravitational forces on each other have relatively simple dynamics: the forces scale as the square of the distance between the objects. A three-body system, however, cannot be solved analytically (it is nonintegrable), which indicates that the dynamics involve a mixture of regularity and chaos. Add to that the constraints of quantum mechanics, and things get truly challenging. Now, an investigation into the transition from quantum dynamics to chaos in the spectrum of helium has shed a little bit of light on one of physics's blackest boxes--quantum chaos.

Read the full story at http://www-als.lbl.gov/als/science/sci_archive/47Qchaos.html.

Publication about this research: R. Püttner, B. Grémaud, D. Delande, M. Domke, M. Martins, A.S. Schlachter, and G. Kaindl, "Statistical Properties of Inter-Series Mixing in Helium: From Integrability to Chaos," Phys. Rev. Lett. 86, 3747 (2001).

2. MOLECULAR FOUNDRY WORKSHOP ANNOUNCED
(Contact: MDAlper@lbl.gov)

A workshop to explore the future of nanoscience research and plan for the Berkeley Lab Molecular Foundry will be held in Berkeley on April 4-5, 2002. The Molecular Foundry will be a Department of Energy user facility based on the premise that nanoscience research, both "hard" and "soft," is advancing beyond the synthesis and characterization of nanostructured "building blocks" to the construction of complex functional assemblies of those building blocks. Success will require that investigators have a breadth of facilities available to them: physicists will need living cells, biologists will need nanofabrication and lithography, and all will need theory. The Berkeley Lab Molecular Foundry will meet these needs as a state-of-the-art, multidisciplinary user facility staffed by professionals and open to researchers from university, industrial, and government laboratories.

The workshop will be divided into two sessions. The first session will be dedicated to plenary talks by internationally recognized leaders in the field, exploring the challenges facing the construction of multicomponent functional structures and devices. The second session will be dedicated to small group meetings in which attendees will discuss their views on how Foundry facilities can be designed and operated to be of greatest value to them. This will be an especially important session because the Department of Energy has provided, in the FY 2002 budget, substantial funding to begin the design of the Foundry, and this is the most critical time to hear advice from the community.

To indicate your interest in the workshop and ensure that you receive future announcements, fill out the online interest form available at http://foundry.lbl.gov/.

3. NEW CONCEPT ENHANCES STXM PERFORMANCE AT BEND-MAGNET BEAMLINE
(Contact: harald_ade@ncsu.edu)

A new scanning transmission x-ray microscope (STXM) has been conceived, built, and commissioned at Beamline 5.3.2, which is optimized for carbon, nitrogen, and oxygen NEXAFS. The new STXM design utilizes laser interferometry to control the relative positions of the x-ray optics (a zone plate) and the sample. It provides perfect registration between sets of images at different photon energies with a spatial resolution of 40 nm. The intense, high-energy-resolution illumination of Beamline 5.3.2 and the advanced, interferometry-based instrument make it possible to perform STXM successfully at ALS bend-magnet beamlines.

With previous systems, one could obtain images at a fixed photon energy with close to diffraction-limited resolution, but the effective resolution suffered in applications that required the use of a range of photon energies. Over a typical C 1s NEXAFS scan from 280 to 310 eV, the zone-plate focal length changes by up to 300 micrometers, requiring displacement of the zone plate along the x-ray beam by this amount without disturbing the lateral position of the zone plate relative to the sample. Mechanical systems able to achieve the required precision are exceptional; indeed, experience has shown that spatial resolution in point spectral mode at existing facilities is rarely better than 200 nm and is sometimes much worse. Data processing to correct for misalignments in image sequences taken at many photon energies provides a partial solution, but this incurs a time penalty and generally exhibits a residual degradation in spatial resolution.

The solution developed at the ALS is to introduce a two-dimensional, differential laser interferometer that continuously monitors the relative (x,y) position of the zone plate and the sample. The interferometer is used as part of the feedback control loop for the fast mechanical stage used to scan the sample when making images. This system not only eliminates energy-to-energy image position errors but also helps to desensitize the microscope to vibrational or other environmental noise. For details regarding the first results, see http://www.physics.ncsu.edu/stxm/p-stxm-first-results.pdf. The laser-interferometer concept is also being incorporated into a STXM upgrade now being commissioned at Beamline 7.0.1.

Members of the Beamline 5.3.2 STXM development team include Harald Ade and David Kilcoyne (North Carolina State Univ.); Tony Warwick, Keith Franck, Howard Padmore, Erik Anderson, and Bruce Harteneck (Berkeley Lab); and Adam Hitchcock, Tolek Tyliszczak, and Peter Hitchcock (McMaster Univ.). This project is funded by DOE, NSF, NSERC, and The Dow Chemical Company.

4. CALL FOR ABSTRACTS: ALS COMPENDIUM 2001
(Contact: LSTamura@lbl.gov)

Every year, the ALS publishes a compendium of abstracts describing the work done, in whole or in part, at the ALS during the past calendar year. All users or user groups (including ALS staff members) should submit a one- to three-page abstract (including figures) describing each project conducted at the ALS during calendar year 2001 (January 1 to December 31), whether published, unpublished, or in progress. The submission deadline is January 28, 2002. Detailed information on submitting abstracts can be found online at http://alspubs.lbl.gov/Compendium_old.

The abstracts received will be published on a CD that will be included in the back of the 2001 ALS Activity Report. Like last year, we will again accept electronic files in a number of formats, preferably PDF. The ALS thanks you for your cooperation in this effort to demonstrate the breadth, depth, and importance of the ALS scientific program. If you have any questions, please contact Lori Tamura by email (LSTamura@lbl.gov), fax (510-495-2111), or phone (510-486-6172).

5. WHO'S IN TOWN: A SAMPLING OF ALS USERS

Following are some of the experimenters who will be collecting data during the next two weeks at the ALS.

Beamline 1.4.3
Hoi-Ying Holman (Berkeley Lab)
Tom Breunig, Dan Fried (Univ. of California, San Francisco)
Felicia Betancourt (Berkeley Lab)
Ted Raab (Carnegie Institution of Washington)

Beamlines 5.0.1, 5.0.2, and 5.0.3
Andre Hoelz (The Rockefeller Univ.)
Bhushan Nagar (Univ. of California, Berkeley)
Glen Spraggon, Andreas Kreusch, Michael Mathews, Dan McMullan (Genomics Institute of the Novartis Research Foundation)
Frank G. Whitby, Perry Brown (Univ. of Utah)
Shengfeng Chen, Weiru Wang, Dong Hae Shin (Berkeley Structural Genomics Center)
Dan Knighton, Hans Parge (Pfizer, Inc.)
Derek Piper, Jinsong Liu, Athena Sudom, Zhulun Wang (Tularik, Inc.)
Armando Villasenor, Mark Knapp (Roche Bioscience)
Jill Cupp-Vickery, Janos K. Lanyi, Hartmut Luecke (Univ. of California, Irvine)
Doug Dougan, Les Tari (Syrrx, Inc.)
Rune Hartmann (The Cleveland Clinic Foundation)

Beamline 6.3.2
Paul Boerner (Stanford Univ.)

Beamline 7.0.1
Brian Tonner (Univ. of Central Florida)
Ivan Schuller (Univ. of California, San Diego)
Stephen Urquhart (Univ. of Saskatchewan, Canada)
Satish Myneni (Princeton Univ.)

Beamline 7.3.3
Baker Farangis (Berkeley Lab)

Beamline 8.0.1
Alexander Moewes (Univ. of Saskatchewan, Canada)

Beamline 10.3.2
Alain Manceau, Frederic Panfili, Geraldine Sarret (Univ. Joseph Fourier, France)
Elizabeth Pilon-Smits (Colorado State Univ.)

6. BERKELEY LAB TO CLOSE FOR HOLIDAYS

Berkeley Lab will shut down on the evening of December 21 and reopen on the morning of January 2. During the closure, the Lab will shut down as much heating and ventilating equipment as possible to reduce costs. However, power to the ALS building will be maintained, and the last user run of 2001 extends through December 23. Anyone having to work on site during this time will need a current ID badge and parking permit to gain access. The User Services Office will provide badging only until 4 p.m. on December 21. Unbadged visitors must have been verified and cleared through the gate by an appropriate host prior to entry. The first user run of 2002 will be January 4 - 7. The next issue of ALSNews will be published on January 23. We wish you all a pleasant and relaxing holiday season.

7. OPERATIONS UPDATE
(Contact: Lampo@lbl.gov)

For the user runs of November 27 - December 3 and December 4 - 9, the beam reliability (time delivered/time scheduled) was 95%. Of the scheduled beam, 80% was delivered to completion without interruption. There were no significant outages.

Long-term and weekly operations schedules are available on the Web (http://www-als.lbl.gov/als/accelinfo.html). Requests for special operations use of the "scrubbing" shift should be sent to Bruce Samuelson (BCSamuelson@lbl.gov, x4738) by 1:00 p.m. Friday. The Accelerator Status Hotline at (510) 486-6766 (ext. 6766 from Lab phones) features a recorded message giving up-to-date information on the operational status of the accelerator.

LBNL/PUB-848
Editors: lstamura@lbl.gov, alrobinson@lbl.gov, amgreiner@lbl.gov

This work was supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC03-76SF00098.