Argonne National Laboratory, the first U.S. national researchlaboratory, located inArgonne,Illinois, some 40 km (25 miles) southwest ofChicago, and operated by theUniversity of Chicago for theU.S. Department of Energy. It was founded in 1946 to conduct basicnuclear physics research and to develop the technology for peaceful uses ofnuclear energy. Argonne National Laboratory now supports more than 200 basic and applied research programs—in science, engineering, and technology—that are directed to maintain basic scientific leadership, guide energy-resource development, improve nuclear-energy technology, and promote environmental-risk management.

The Argonne laboratory houses several major research facilities that are available for collaborative and interdisciplinary use by government, academic, and industrial scientists. Four of these facilities—theAdvanced Photon Source (APS), theIntense Pulsed Neutron Source (IPNS), theArgonne Tandem Linear Accelerator System (ATLAS), and theHigh-Voltage Electron Microscope- (HVEM-)Tandem Facility—have been designated official U.S. Department of Energy National User Facilities.

The APS, which opened in 1996, is a 7-gigaelectron volt (GeV)synchrotronparticle accelerator that is designed to produce brilliant (highly collimated) and intense beams of high-energyX-raysynchrotron radiation for advanced X-ray imaging anddiffraction studies. Using the APS, scientists have performedX-ray diffraction analyses to unravel the structures of complex biological supramolecular assemblies, includingribosomes,enzyme-inhibitor (drug) complexes, and bacterialtoxins.

ATLAS is a superconductinglinear accelerator that accelerates beams of heavyions up to and includinguranium for high-energynuclear physics research. One example of this work involves experiments toprobe the details of nuclear structure in order to answer fundamental questions concerningnuclear stability. The IPNS provides a powerful source ofneutrons for neutron-scattering experiments inmaterials science research; applications include high-temperatureceramics and advanced superconducting materials. The HVEM-Tandem Facility combineselectron microscopy with ion-beam irradiation to study, for example, high-temperaturesuperconductors.