Bonn 2010 – wissenschaftliches Programm
T 102.5: Vortrag
Dienstag, 16. März 2010, 17:45–18:00, HG XII
Energy calibration of very inclined air showers — •Hans Dembinski1, Markus Roth2, and Thomas Hebbeker3 — 1Institut für experimentelle Kernphysik, Karlsruher Institut für Technologie (KIT), Karlsruhe — 2Institut für Kernphysik, Karlsruher Institut für Technologie (KIT), Karlsruhe — 3III. Physikalisches Institut A, RWTH Aachen University, Aachen
The Pierre Auger Observatory detects extensive air showers which are initiated by ultra-high energy cosmic rays. The properties of the cosmic rays are derived indirectly from the air shower observation.
The surface detector of the observatory is well suited to detect showers with zenith angles from 0∘ to 90∘. Standard analyses focus on so called vertical showers with inclinations smaller than 60∘. Showers with larger zenith angles are called very inclined showers. Both have distinct experimental signatures which require separate event reconstructions.
The ground signal of very inclined air showers is muon dominated and the energy reconstruction uses the variable Rµ as an estimator for the cosmic ray energy which is proportional to the total number of muons Nµ on the ground. The talk will focus on the energy calibration of Rµ with events observed simultaneously in the surface and fluorescence detector of the observatory. This calibration procedure also offers the unique opportunity to derive the shower-to-shower fluctuations of Rµ which are sensitive to the cosmic ray mass composition.