A Study of the Effect of Molecular and Aerosol Conditions in the Atmosphere on Air Fluorescence Measurements at the Pierre Auger Observatory

J. ABRAHAM (GARCIA, B. Y 400 AUTORES DE LA COL. INTERNACIONAL PIERRE AUGER)

ASTROPARTICLE PHYSICS

Elsevier

Lugar: Amsterdam; Año: 2010 vol. 33 p. 108 - 128

0927-6505

The air fluorescence detector of the Pierre Auger Observatory is designed toperform calorimetric measurements of extensive air showers created by cosmicrays of above 1018 eV. To correct these measurements for the effects introducedby atmospheric fluctuations, the Observatory contains a group of monitoringinstruments to record atmospheric conditions across the detector site, an areaexceeding 3,000 km2. The atmospheric data are used extensively in thereconstruction of air showers, and are particularly important for the correctdetermination of shower energies and the depths of shower maxima. Thispaper contains a summary of the molecular and aerosol conditions measuredat the Pierre Auger Observatory since the start of regular operations in 2004,and includes a discussion of the impact of these measurements on air showerreconstructions. Between 1018 and 1020 eV, the systematic uncertainties dueto all atmospheric effects increase from 4% to 8% in measurements of showerenergy, and 4 g cm−2 to 8 g cm−2 in measurements of the shower maximum.