Electron–muon identification by atmospheric shower in a new concept of an EAS detector

We show the test results for TOF resolution and μ / e separation capabilities of a prototype element (Iori and Sergi, 2008 [1]), intended for deployment in an array capable of measuring large zenith angle cosmic rays as well as detecting the signature of Ultra High Energy tau neutrino interactions using the Earth skimming strategy (Fargion et al., 2004 [2], Feng et al., 2002 [3], Beacom et al., 2003 [4], Zas, 2005 [5]). The module was designed to recognize single particles and determine the direction of motion (up/down) and measure the trajectory angles. It uses two pairs of scintillator counters, named towers, each composed by two tiles (20×20 cm2, 1.4 cm thick), separated by 160 cm. Each tile is read by one low voltage R5783 Hamamatsu photomultiplier (PMT). Two PMT boxes are attached to a metal structure that defines the axis of the array. Each tile is embedded in a PVC box which also contains the PMT. The PMT has excellent time resolution ( ≈ 400 ps ) for good TOF precision. The PMT signal was digitized by the MATAQ board in coincidence with KASCADE-GRANDE (KG) shower Delagnes and Breton, 2001 [6].