Observation of γ-sources using a new reconstruction technique in the CLUE experiment

Abstract

The CLUE experiment, located in La Palma island at 2200 m a.s.l., is an array of 3×3 telescope, detecting the UV (190 – 230 nm) Čerenkov light produced by atmospheric showers. Since atmospheric absorption in the UV range is higher than in the visible range, CLUE cannot apply existing algorithms normally used in IACT experiments to determine primary cosmic ray direction. In this paper we present a new method developed by CLUE. The algorithm performances were evaluated using simulated showers. Using the new technique, preliminary results of last two years observational campaigns on the Crab Nebula and on Markarian 421 are presented, showing a clear signal on both sources. The CLUE experiment collected also data with the telescopes aiming directly at the Moon: we expect improvements also on the Moon Shadow measurement adopting the new method.