Argonne's Advanced Photon Source opens new scientific horizons

ARGONNE, Ill. (May 1, 1996) -- New horizons in biological and materials research were opened today at the U.S. Department of Energy's Argonne National Laboratory with the dedication of a machine capable of producing the world's most brilliant X-ray beams for research.

Scientists and engineers at Argonne's Advanced Photon Source (APS) celebrated the dawning of a new era in X-ray research after nearly a decade of planning and building. Scientists from 100 universities, 36 companies and 27 research institutes have already signed up to conduct research at the APS.

"Thanks to this new facility, we can expect advances in the areas of medicine, biotechnology and materials -- creating America's jobs, products and industries of the future," said President Bill Clinton. "The Advanced Photon Source demonstrates the successful partnership of private companies, the research community, and federal and state governments to help create that future."

Secretary of Energy Hazel O'Leary formally dedicated the facility. DOE has invested $812 million in the APS, including construction, commissioning and operating costs. In addition, universities, industry and other federal agencies have contributed $160 million in design and instrumentation for beamlines, and the state of Illinois provided $19 million for construction of a user residence facility at the Argonne site. The five-year APS construction project was completed on budget and ahead of schedule.

The X-rays are produced in a huge donut-shaped machine, 3,640 feet in circumference, large enough to encircle Chicago's Wrigley Field. Scientists from across the country are beginning experiments in a range of materials, biomolecular, chemical and environmental research projects. The work is conducted by collaborative access teams, each made up of dozens of researchers from a variety of institutions that have committed their own funding and resources in designing and building instruments at the APS.

X-rays in research

For 100 years, X-rays have been ideal for revealing what visible light can't -- for seeing through "impossible" barriers. One of the first X-ray photographs showed the image of bones in a living person for the first time. That photograph was taken in 1895 by Wilhelm Roentgen, the physicist who had just discovered the strange new form of radiation.

In the last century, scientists have come to depend on X-rays to reveal the world around and within us. Within a few months of Roentgen's discovery, X-rays were being used in many ways, providing a powerful new tool in medical diagnosis. Scientists have since learned how to use the radiation to probe amazing intricacies: the atomic structure of biological molecules such as proteins or DNA, the chemical reactions and processes that occur as polymers and ceramics form, and even the detailed crystalline structure of most elements. One hundred years after Roentgen's discovery, the APS will give the scientific community the most powerful X-ray beams ever created for these kinds of research, allowing scientists to probe more deeply and reveal more detail than ever before.

X-rays are a form of invisible electromagnetic radiation, very similar to the light that our eyes can see. All electromagnetic radiation, including radio waves, microwaves, visible light and X-rays, is made up of discrete packets of energy called photons. The photons travel at the speed of light with different wavelengths and energies characteristic of different kinds of radiation. X-rays have much higher energies and much shorter wavelengths than visible light. These shorter wavelengths can penetrate into and distinguish details visible light can't, just as a sharp probe can fit into and reveal information about smaller shapes than a blunt one.

How APS works

The focus at APS, since groundbreaking in 1990, has been on developing, building and putting in place the technology to make the machine work. Such bright X-rays have never been produced or controlled to the extent of those at the APS. The beam must be aimed with the precision of less than a micron -- about one-tenth the thickness of a human hair. Argonne researchers have developed a device that can tell if the beam is on target while withstanding the searing heat that the X-rays generate.

To generate a constant-intensity X-ray beam for long periods of time, the APS circulates a beam of positrons (positively charged electrons) through a storage ring. The positrons must circulate without striking anything, even something as small as a gas molecule, or they will scatter. The storage ring's vacuum system, developed at Argonne, will remove all but one atom out of every trillion present in normal atmosphere.

The APS produces "hard" X-rays -- X-rays with extremely short wavelengths and energies from tens of thousands to hundreds of thousands of electron volts -- enough energy to break free even the tightest-bound electrons from an atom. In addition, the APS X-ray beams will be 10,000 times more brilliant than most other sources.

Brighter light reveals more details in structure and allows faster image-taking. A photographer attempting to photograph in dim light uses a slow shutter speed to allow time for more light to reach the photographic film. In bright light, much faster shutter speeds are possible. Often bright-light pictures are sharper, because they capture a shorter moment in time. In the same way, sharper, more detailed images of materials from proteins to ceramics will be possible with the brighter light of the APS.

With such fast picture-taking abilities, scientists will make motion pictures of chemical processes in action. APS X-ray beams can be pulsed like a strobe light to capture images of the intermediate arrangements of atoms and molecules as they react with one another and change shape.

These microscopic movies will allow biological and medical researchers to see the movements of every atom in an enzyme as it catalyzes a chemical reaction. Enzymes help control most of the chemical reactions that take place in the human body.

Such studies will increase science's knowledge of basic biochemical processes such as photosynthesis, DNA replication and protein synthesis. They will also help molecular biologists design "smart" pharmaceuticals that can find the right place to attach to specific enzymes, thereby either blocking or enhancing their action in the body.

Discoveries made at the APS are expected to enhance the quality of daily life and to improve the nation's economic and technological future. Advances are expected particularly in biotechnology, polymer and advanced materials, medical diagnostics, digital imaging techniques, semiconductor materials and microelectronic circuits.

Construction of the 959,000 square foot facility required 54,600 cubic yards of concrete; 5,800 tons of structural steel; and 2 million linear feet of wire.

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation's first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America 's scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy's Office of Science.

For more information, please contact Steve McGregor (630/252-5580 or media@anl.gov) at Argonne.