33RD INTERNATIONAL COSMIC RAY CONFERENCE, RIO DE JANEIRO 2013 THE ASTROPARTICLE PHYSICS CONFERENCE MAGIC discovery and multiwavelength observations of the BL Lac 1ES

Abstract: Blazars, active galactic nuclei whose jet axis is pointed towards the observer, constitute the most numerous class of extragalactic very high energy (VHE, E>100 GeV) γ-ray emitters. The MAGIC experiment, a system of two Imaging Atmospheric Cherenkov Telescopes located in the Canary Island of La Palma (Northern hemisphere), with an energy threshold of 50 GeV is a well suited experiment for observations of such objects. Here we present the discovery of the BL Lac 1ES 1727+502 (z = 0.055) as VHE source. This object was identified as a promising TeV candidate based on archival data and the observation that lead to this detection was not triggered by any high state alert in other wavebands. Our data are complemented with multiwavelength observations: optical data from the KVA telescope, UV, optical and X-ray archival data taken with the instruments on board the Swift satellite and high energy (HE, 300 MeV< E < 100 GeV) data from the Fermi-LAT instrument. We studied the spectral energy distribution of 1ES 1727+502 and interpreted it with a one-zone synchrotron self-Compton model with parameters that are typical for this class of sources