Bibcode
Aleksić, J.; Ansoldi, S.; Antonelli, L. A.; Antoranz, P.; Arcaro, C.; Babic, A.; Bangale, P.; Barres de Almeida, U.; Barrio, J. A.; Becerra González, J.; Bednarek, W.; Bernardini, E.; Biasuzzi, B.; Biland, A.; Blanch, O.; Bonnefoy, S.; Bonnoli, G.; Borracci, F.; Bretz, T.; Carmona, E.; Carosi, A.; Colin, P.; Colombo, E.; Contreras, J. L.; Cortina, J.; Covino, S.; Da Vela, P.; Dazzi, F.; De Angelis, A.; De Caneva, G.; De Lotto, B.; de Oña Wilhelmi, E.; Delgado Mendez, C.; Di Pierro, F.; Dominis Prester, D.; Dorner, D.; Doro, M.; Einecke, S.; Eisenacher, D.; Elsaesser, D.; Fernández-Barral, A.; Fidalgo, D.; Fonseca, M. V.; Font, L.; Frantzen, K.; Fruck, C.; Galindo, D.; García López, R. J.; Garczarczyk, M.; Garrido Terrats, D.; Gaug, M.; Godinović, N.; González Muñoz, A.; Gozzini, S. R.; Hadasch, D.; Hanabata, Y.; Hayashida, M.; Herrera, J.; Hose, J.; Hrupec, D.; Idec, W.; Kadenius, V.; Kellermann, H.; Knoetig, M. L.; Kodani, K.; Konno, Y.; Krause, J.; Kubo, H.; Kushida, J.; La Barbera, A.; Lelas, D.; Lewandowska, N.; Lindfors, E.; Lombardi, S.; Longo, F.; López, M.; López-Coto, R.; López-Oramas, A.; Lorenz, E.; Lozano, I.; Makariev, M.; Mallot, K.; Maneva, G.; Mannheim, K.; Maraschi, L.; Marcote, B.; Mariotti, M.; Martínez, M.; Mazin, D.; Menzel, U.; Miranda, J. M.; Mirzoyan, R.; Moralejo, A.; Munar-Adrover, P.; Nakajima, D.; Neustroev, V.; Niedzwiecki, A.; Nievas Rosillo, M.; Nilsson, K.; Nishijima, K. et al.
Bibliographical reference
Astronomy and Astrophysics, Volume 591, id.A10, 14 pp.
Advertised on:
6
2016
Journal
Citations
23
Refereed citations
23
Description
Context. 1ES 1011+496 (z = 0.212) was discovered in very high-energy
(VHE, E> 100 GeV) γ rays with MAGIC in 2007. The absence of
simultaneous data at lower energies led to an incomplete
characterization of the broadband spectral energy distribution (SED).
Aims: We study the source properties and the emission mechanisms,
probing whether a simple one-zone synchrotron self-Compton (SSC)
scenario is able to explain the observed broadband spectrum.
Methods: We analyzed data in the range from VHE to radio data from 2011
and 2012 collected by MAGIC, Fermi-LAT, Swift, KVA, OVRO, and
Metsähovi in addition to optical polarimetry data and radio maps
from the Liverpool Telescope and MOJAVE. Results: The VHE
spectrum was fit with a simple power law with a photon index of 3.69
± 0.22 and a flux above 150 GeV of (1.46 ± 0.16) ×
10-11 ph cm-2 s-1. The source 1ES
1011+496 was found to be in a generally quiescent state at all observed
wavelengths, showing only moderate variability from radio to X-rays. A
low degree of polarization of less than 10% was measured in optical,
while some bright features polarized up to 60% were observed in the
radio jet. A similar trend in the rotation of the electric vector
position angle was found in optical and radio. The radio maps indicated
a superluminal motion of 1.8 ± 0.4 c, which is the highest speed
statistically significant measured so far in a high-frequency-peaked BL
Lac. Conclusions: For the first time, the high-energy bump in the
broadband SED of 1ES 1011+496 could be fully characterized from 0.1 GeV
to 1 TeV, which permitted a more reliable interpretation within the
one-zone SSC scenario. The polarimetry data suggest that at least part
of the optical emission has its origin in some of the bright radio
features, while the low polarization in optical might be due to the
contribution of parts of the radio jet with different orientations of
the magnetic field with respect to the optical emission.