PG 1553+113: five years of observations with MAGIC
Abstract
We present the results of five years (2005-2009) of MAGIC observations of the BL Lac object PG 1553+113 at very high energies (VHEs, E > 100 GeV). Power law fits of the individual years are compatible with a steady mean photon index \Gamma = 4.27 0.14. In the last three years of data, the flux level above 150 GeV shows a clear variability (probability of constant flux < 0.001%). The flux variations are modest, lying in the range from 4% to 11% of the Crab Nebula flux. Simultaneous optical data also show only modest variability that seems to be correlated with VHE gamma ray variability. We also performed a temporal analysis of (all available) simultaneous Fermi/LAT data of PG 1553+113 above 1 GeV, which reveals hints of variability in the 2008-2009 sample. Finally, we present a combination of the mean spectrum measured at very high energies with archival data available for other wavelengths. The mean spectral energy distribution can be modeled with a one-zone Synchrotron Self Compton (SSC) model, which gives the main physical parameters governing the VHE emission in the blazar jet.
Keywords
Cite
@article{arxiv.1101.2764,
title = {PG 1553+113: five years of observations with MAGIC},
author = {MAGIC Collaboration and J. Aleksić and E. A. Alvarez and L. A. Antonelli and P. Antoranz and M. Asensio and M. Backes and J. A. Barrio and D. Bastieri and J. Becerra González and W. Bednarek and A. Berdyugin and K. Berger and E. Bernardini and A. Biland and O. Blanch and R. K. Bock and A. Boller and G. Bonnoli and D. Borla Tridon and I. Braun and T. Bretz and A. Cañellas and E. Carmona and A. Carosi and P. Colin and E. Colombo and J. L. Contreras and J. Cortina and L. Cossio and S. Covino and F. Dazzi and A. De Angelis and G. De Caneva and E. De Cea del Pozo and B. De Lotto and C. Delgado Mendez and A. Diago Ortega and M. Doert and A. Domínguez and D. Dominis Prester and D. Dorner and M. Doro and D. Elsaesser and D. Ferenc and M. V. Fonseca and L. Font and C. Fruck and R. J. García López and M. Garczarczyk and D. Garrido and G. Giavitto and N. Godinović and D. Hadasch and D. Häfner and A. Herrero and D. Hildebrand and D. Höhne-Mönch and J. Hose and D. Hrupec and B. Huber and T. Jogler and H. Kellermann and S. Klepser and T. Krähenbühl and J. Krause and A. La Barbera and D. Lelas and E. Leonardo and E. Lindfors and S. Lombardi and M. López and A. López-Oramas and E. Lorenz and M. Makariev and G. Maneva and N. Mankuzhiyil and K. Mannheim and L. Maraschi and M. Mariotti and M. Martínez and D. Mazin and M. Meucci and J. M. Miranda and R. Mirzoyan and H. Miyamoto and J. Moldón and A. Moralejo and P. Munar-Adrover and D. Nieto and K. Nilsson and R. Orito and I. Oya and D. Paneque and R. Paoletti and S. Pardo and J. M. Paredes and S. Partini and M. Pasanen and F. Pauss and M. A. Perez-Torres and M. Persic and L. Peruzzo and M. Pilia and J. Pochon and F. Prada and P. G. Prada Moroni and E. Prandini and I. Puljak and I. Reichardt and R. Reinthal and W. Rhode and M. Ribó and J. Rico and S. Rügamer and A. Saggion and K. Saito and T. Y. Saito and M. Salvati and K. Satalecka and V. Scalzotto and V. Scapin and C. Schultz and T. Schweizer and M. Shayduk and S. N. Shore and A. Sillanpää and J. Sitarek and D. Sobczynska and F. Spanier and S. Spiro and V. Stamatescu and A. Stamerra and B. Steinke and J. Storz and N. Strah and T. Surić and L. Takalo and H. Takami and F. Tavecchio and P. Temnikov and T. Terzić and D. Tescaro and M. Teshima and O. Tibolla and D. F. Torres and A. Treves and M. Uellenbeck and H. Vankov and P. Vogler and R. M. Wagner and Q. Weitzel and V. Zabalza and F. Zandanel and R. Zanin and S. Buson and D. Horan and S. Larsson and F. D'Ammando},
journal= {arXiv preprint arXiv:1101.2764},
year = {2015}
}
Comments
11 pages, 6 figures, accepted for publication in ApJ