XAFS at the Pacific Northwest Consortium-Collaborative Access Team undulator beamline

The Pacific Northwest Consortium-Collaborative Access Team (PNC-CAT) has be gun operating an insertion device beamline at the Advanced Photon Source. T he beamline has been extensively used for XAFS studies. This paper summariz es its capabilities, and our initial operational experience. The beamline i s based on APS undulator A, and incorporates full undulator scanning. The m onochromator is liquid nitrogen cooled and has both Si(111) and Si(311) cry stals in a side-by-side configuration. Crystal changes only take a few minu tes. The crystals cover the energy range from 3-50 keV with fluxes as high as 2x10(13) ph/sec. Microbeams can be produced using Kirkpatrick-Baez mirro rs (spot size 1-3 mm) or tapered capillaries (sub-mm spots). When these opt ics are combined with a 13-element Ge detector, the beamline provides power ful microbeam imaging and spectroscopy capabilities. Experimental examples from the environmental field and in-situ UHV film growth will be discussed.