Advanced Photon Source
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Image:Advanced Photon Source aeri.jpg The Advanced Photon Source (APS) at Argonne National Laboratory is a national synchrotron-radiation light source research facility funded by the United States Department of Energy, Office of Science, Office of Basic Energy Sciences. Argonne National Laboratory is managed by the University of Chicago for the U.S. DOE.
Using high-brilliance X-ray beams from the APS, members of the international synchrotron-radiation research community conduct forefront basic and applied research in the fields of materials science, biological science, physics, chemistry, environmental, geophysical, planetary science, and innovative X-ray instrumentation.
How APS works
Electrons are produced by a cathode that is heated to about 1,100°C (2,000°F). The electrons are accelerated to 99.999% of the speed of light in a linear accelerator.Template:Ref From the linear accelerator, the electrons are injected into the booster synchrotron. Here, the electrons are sent around an oval racetrack of electromagnets, providing further acceleration. Within one-half second, the electrons reach 99.999999% of the speed of light.Template:Ref Upon reaching this speed, the electrons are injected into the storage ring, a 1104 meter (3 622 ft) circumference ring of more than 1,000 electromagnets.Template:Ref
Once in the storage ring, the electrons are available for use in experimentation. Around the ring are 40 straight sections. Five of these sections are used to inject electrons into the ring. The remaining 35 straight sections are equipped with insertion devices. Insertion devices, usually wigglers or undulators, cause electrons to wobble through the section, thus emitting light. Due to the relativistic velocities of the electrons, that light is Lorentz contracted into the x-ray band of the electromagnetic spectrum.Template:Ref
The Experiment Hall surrounds the storage ring and is divided into 35 sectors, each of which has access to x-ray beamlines, one at an insertion device, and the other at a bending magnet.Template:Ref Each sector also has a lab/office module offering immediate access to the beamline.Template:Ref
 Booster synchotron section |
 Insertion device |
 Linear Accelrator |
 Storage ring section |
References
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Insertion devices do not "direct electrons into an experiment". They cause the electron beam to wiggle rapidly. Those wiggling electrons produce x-rays, and the x-rays go down the beamlines to the user experiments. The electrons continue to circulate around the storage ring.