30TH INTERNATIONAL COSMIC RAY CONFERENCE HEAT – Enhancement Telescopes for the Pierre Auger Southern Observatory

The southern part of the Pierre Auger Observatory (PAO) is nearing completion in the province of Mendoza, Argentina. Since 2004 the instrument is used to take air shower data at the highest energies [1]. The energy threshold of the 3000 km2 surface array of 1600 particle detectors for high quality air shower reconstruction is about 3 . 10 eV. The 24 Auger fluorescence telescopes (FD), located in four “eye” stations at the edge of the detector array, enable precise air shower measurements even at primary energies below 10 eV. The Auger Collaboration has decided to further expand its energy range down to 10 eV after completion of the southern observatory around the end of 2007 by three additional fluorescence telescopes with an elevated field of view from 30 to 60 above the horizon. It is foreseen to use these High Elevation Auger Telescopes (HEAT) in combination with the existing telescopes at one of the four existing FD sites (Coihueco) as well as in hybrid mode using the shower particle data from a new infill detector area of about 25 km2 with fourfold sampling density – close to HEAT and in the field of view of the new telescopes. This SD infill array (AMIGA) will also be equipped with large area muon detectors [2]. In addition, it will be a perfectly suited test area for the development of novel detection techniques for air showers at ultrahigh energies [3].