Extracting first science measurements from the southern detector of the Pierre Auger observatory

The worldʹs largest cosmic-ray detector is nearing completion in the remote Pampas of Argentina. This instrument measures extensive air-showers with energies from 10 18 to 10 20 eV and beyond. A surface detector array of area 3000 km 2 records the lateral distribution of charged particles at ground level. A fluorescence detector overlooking the surface detector records the longitudinal light profiles of showers in the atmosphere to make a calorimetric energy measurement. A “test beam” for the fluorescence detector is generated by a calibrated laser near the array center. This talk will focus on detector characterizations essential to the first science results that have been reported from the observatory. Plans to construct a larger instrument in the northern hemisphere will also be outlined.