Významné výsledky oddělení 16

The paper is based on the long-period data acquired by the Pierre Auger Observatory. The presented results concern the analysis of the unique data set encompassing 4000 atmospheric air showers detected simultaneously by the surface and fluorescence detectors, while the observed parameter was the depth of shower maximum estimated from the fluorescence detector measurement. A transition from light to heavy elements with increasing energy is observed in the spectrum of incoming primary cosmic rays.

The atmospheric monitoring program of the Pierre Auger Observatory allows for a targeted measurement of atmospheric conditions shortly after the detection of air showers of special interest to improove especially the fluorescence detector reconstruction of such events. The paper reports on the implementation of the rapid monitoring program and its status. The rapid monitoring program is found to have a potential for supporting dedicated physics analyses beyond the standard event reconstruction.