Earth Science Study At Argonne Intensifies

e circular Experiment Hall at Argonne National Laboratory's Advanced Photon Source (APS) accelerator is so large that it could encircle Chicago's U.S. Cellular Field. Inside the hall are 35 individual "sectors" with laboratories equipped to tap the x-rays that are emitted by the electrons racing around the ring. Each sector typically has at least two x-ray beamlines on which to conduct experiments.