March 29, 2000

"Trip to the Light Fantastique"

SMSI members will tour Argonne National Laboratory's Advanced Photon Source.

The Advanced Photon Source at Argonne National Laboratory is the world's premier multiuser facility for research with X-ray synchrotron radiation. The APS is based on a 7 GEV synchrotron storage ring that supports numerous high brilliance X-ray sources, beam transport lines, and associated experimental stations. These X-ray sources, known as undulators and wigglers, provide highly collimated, tunable, partially coherent X-ray beams to the experimental stations in up to 38 sectors around the ring. Sector two is dedicated to X-Ray Microscopy.

As a national user facility for research in fields as diverse as biotechnology, oil, medical imaging, computers, steel, waste management, communications, defense, transportation, and nuclear energy to name a few, the APS is expected to stimulate rapid advances in American industrial research.

SMSI Meeting of March 29, 2000

The SMSI meeting for March took place at the Advanced Photon Source at Argonne National Laboratory. After enjoying a catered dinner, the group was divided into two tour sized groups which were guided into the APS to see and hear about a truly extraordinary scientific installation. Having viewed the main control room, our group headed for sector one where we first literally enjoyed an overview of a portion of the storage ring and one of the many beamlines available for experimental work.

Although even a bare bones sketch of the Advanced Photon Source is beyond the scope of this article, it is interesting to note that since we last heard about the APS at SMSI they have converted from the use of positrons to electrons after realizing that, at the energies involved, anticipated problems with electrons are actually insignificant. We also learned that the APS at Argonne will most likely become the first such facility to put into practice the technique of topping up the storage ring beam. This will allow for a virtually uninterrupted beam, which currently has to be recharged to bring it back up to the proper energy level.

Our tour also took us inside one of the "hutches" where an experiment was in the process of being set up. An array of up to thirty motors with micrometer control accuracy provides for the level of precise positioning required for target set up. One had to remind oneself that very close to where we stood a powerful beam raced silently with near light speed energies.

Report submitted by John Macdonald, Recording Secretary