Multifrequency Studies of the Peculiar Quasar 4C +21.35 During the 2010 Flaring Activity
Abstract
The discovery of rapidly variable Very High Energy (VHE; E > 100 GeV) gamma-ray emission from 4C +21.35 (PKS 1222+216) by MAGIC on 2010 June 17, triggered by the high activity detected by the Fermi Large Area Telescope (LAT) in high energy (HE; E > 100 MeV) gamma-rays, poses intriguing questions on the location of the gamma-ray emitting region in this flat spectrum radio quasar. We present multifrequency data of 4C +21.35 collected from centimeter to VHE during 2010 to investigate the properties of this source and discuss a possible emission model. The first hint of detection at VHE was observed by MAGIC on 2010 May 3, soon after a gamma-ray flare detected by Fermi-LAT that peaked on April 29. The same emission mechanism may therefore be responsible for both the HE and VHE emission during the 2010 flaring episodes. Two optical peaks were detected on 2010 April 20 and June 30, close in time but not simultaneous with the two gamma-ray peaks, while no clear connection was observed between the X-ray an gamma-ray emission. An increasing flux density was observed in radio and mm bands from the beginning of 2009, in accordance with the increasing gamma-ray activity observed by Fermi-LAT, and peaking on 2011 January 27 in the mm regime (230 GHz). We model the spectral energy distributions (SEDs) of 4C +21.35 for the two periods of the VHE detection and a quiescent state, using a one-zone model with the emission coming from a very compact region outside the broad line region. The three SEDs can be fit with a combination of synchrotron self-Compton and external Compton emission of seed photons from a dust torus, changing only the electron distribution parameters between the epochs. The fit of the optical/UV part of the spectrum for 2010 April 29 seems to favor an inner disk radius of <6 gravitational radii, as one would expect from a prograde-rotating Kerr black hole.
Keywords
Cite
@article{arxiv.1403.7534,
title = {Multifrequency Studies of the Peculiar Quasar 4C +21.35 During the 2010 Flaring Activity},
author = {M. Ackermann and M. Ajello and A. Allafort and E. Antolini and G. Barbiellini and D. Bastieri and R. Bellazzini and E. Bissaldi and E. Bonamente and J. Bregeon and M. Brigida and P. Bruel and R. Buehler and S. Buson and G. A. Caliandro and R. A. Cameron and P. A. Caraveo and E. Cavazzuti and C. Cecchi and R. C. G. Chaves and A. Chekhtman and J. Chiang and G. Chiaro and S. Ciprini and R. Claus and J. Cohen-Tanugi and J. Conrad and S. Cutini and F. D'Ammando and F. de Palma and C. D. Dermer and E. do Couto e Silva and D. Donato and P. S. Drell and C. Favuzzi and J. Finke and W. B. Focke and A. Franckowiak and Y. Fukazawa and P. Fusco and F. Gargano and D. Gasparrini and N. Gehrels and N. Giglietto and F. Giordano and M. Giroletti and G. Godfrey and I. A. Grenier and S. Guiriec and M. Hayashida and J. W. Hewitt and D. Horan and R. E. Hughes and G. Iafrate and A. S. Johnson and J. Knodlseder and M. Kuss and J. Lande and S. Larsson and L. Latronico and F. Longo and F. Loparco and M. N. Lovellette and P. Lubrano and M. Mayer and M. N. Mazziotta and J. E. McEnery and P. F. Michelson and T. Mizuno and M. E. Monzani and A. Morselli and I. V. Moskalenko and S. Murgia and R. Nemmen and E. Nuss and T. Ohsugi and M. Orienti and E. Orlando and J. S. Perkins and M. Pesce-Rollins and F. Piron and G. Pivato and T. A. Porter and S. Rainò and M. Razzano and A. Reimer and O. Reimer and D. A. Sanchez and A. Schulz and C. Sgrò and E. J. Siskind and G. Spandre and P. Spinelli and L. Stawarz and H. Takahashi and T. Takahashi and J. G. Thayer and J. B. Thayer and D. J. Thompson and M. Tinivella and D. F. Torres and G. Tosti and E. Troja and T. L. Usher and J. Vandenbroucke and V. Vasileiou and G. Vianello and V. Vitale and M. Werner and B. L. Winer and D. L. Wood and K. S. Wood and J. Aleksic and S. Ansoldi and L. A. Antonelli and P. Antoranz and A. Babic and P. Bangale and U. Barres de Almeida and J. A. Barrio and J. Becerra Gonzalez and W. Bednarek and K. Berger and E. Bernardini and A. Biland and O. Blanch and R. K. Bock and S. Bonnefoy and G. Bonnoli and F. Borracci and T. Bretz and E. Carmona and A. Carosi and D. Carreto Fidalgo and P. Colin and E. Colombo and J. L. Contreras and J. Cortina and S. Covino and P. Da Vela and F. Dazzi and A. De Angelis and G. De Caneva and B. De Lotto and C. Delgado Mendez and M. Doert and A. Dominguez and D. Dominis Prester and D. Dorner and M. Doro and S. Einecke and D. Eisenacher and D. Elsaesser and E. Farina and D. Ferenc and M. V. Fonseca and L. Font and K. Frantzen and C. Fruck and R. J. Garcia Lopez and M. Garczarczyk and D. Garrido Terrats and M. Gaug and G. Giavitto and N. Godinovic and A. Gonzalez Munoz and S. R. Gozzini and D. Hadasch and A. Herrero and D. Hildebrand and J. Hose and D. Hrupec and W. Idec and V. Kadenius and H. Kellermann and M. L. Knoetig and K. Kodani and Y. Konno and J. Krause and H. Kubo and J. Kushida and A. La Barbera and D. Lelas and N. Lewandowska and E. Lindfors and S. Lombardi and M. Lopez and R. Lopez-Coto and A. Lopez-Oramas and E. Lorenz and I. Lozano and M. Makariev and K. Mallot and G. Maneva and N. Mankuzhiyil and K. Mannheim and L. Maraschi and B. Marcote and M. Mariotti and M. Martinez and D. Mazin and U. Menzel and M. Meucci and J. M. Miranda and R. Mirzoyan and A. Moralejo and P. Munar-Adrover and D. Nakajima and A. Niedzwiecki and K. Nishijima and K. Nilsson and N. Nowak and R. Orito and A. Overkemping and S. Paiano and M. Palatiello and D. Paneque and R. Paoletti and J. M. Paredes and X. Paredes-Fortuny and S. Partini and M. Persic and F. Prada and P. G. Prada Moroni and E. Prandini and S. Preziuso and I. Puljak and R. Reinthal and W. Rhode and M. Ribo and J. Rico and J. Rodriguez Garcia and S. Rugamer and A. Saggion and T. Saito and K. Saito and M. Salvati and K. Satalecka and V. Scalzotto and V. Scapin and C. Schultz and T. Schweizer and S. N. Shore and A. Sillanpaa and J. Sitarek and I. Snidaric and D. Sobczynska and F. Spanier and V. Stamatescu and A. Stamerra and T. Steinbring and J. Storz and S. Sun and T. Suric and L. Takalo and H. Takami and F. Tavecchio and P. Temnikov and T. Terzic and D. Tescaro and M. Teshima and J. Thaele and O. Tibolla and T. Toyama and A. Treves and P. Vogler and R. M. Wagner and F. Zandanel and R. Zanin and M. F. Aller and E. Angelakis and D. A. Blinov and S. G. Djorgovski and A. J. Drake and N. V. Efimova and M. A. Gurwell and D. C. Homan and B. Jordan and E. N. Kopatskaya and Y. Y. Kovalev and O. M. Kurtanidze and A. Lahteenmaki and V. M. Larionov and M. L. Lister and E. Nieppola and M. G. Nikolashvili and E. Ros and T. Savolainen and L. A. Sigua and M. Tornikoski and .},
journal= {arXiv preprint arXiv:1403.7534},
year = {2015}
}
Comments
46 pages, 10 figures, 4 tables. The Astrophysical Journal, Volume 786, Issue 2, article id. 157, 17 pp. Contact Authors: Filippo D'Ammando, Justin Finke, Davide Donato, Josefa Becerra Gonzalez, Tomislav Terzic. Figure 1 updated