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Testing two-component models on very high-energy gamma-ray-emitting BL Lac objects

Acciari, V. A. and Ansoldi, S. and Antonelli, L. A. and Arbet Engels, A. and Baack, D. and Babić, A. and Banerjee, B. and Barres de Almeida, U. and Barrio, J. A. and Becerra González, J. and Bednarek, W. and Bellizzi, L. and Bernardini, E. and Berti, A. and Besenrieder, J. and Bhattacharyya, W. and Bigongiari, C. and Biland, A. and Blanch, O. and Bonnoli, G. and Bošnjak, Ž. and Busetto, G. and Carosi, R. and Ceribella, G. and Cerruti, M. and Chai, Y. and Chilingarian, A. and Cikota, S. and Colak, S. M. and Colin, U. and Colombo, E. and Contreras, J. L. and Cortina, J. and Covino, S. and D’Amico, G. and D’Elia, V. and Da Vela, P. and Dazzi, F. and De Angelis, A. and De Lotto, B. and Delfino, M. and Delgado, J. and Depaoli, D. and Di Pierro, F. and Di Venere, L. and Do Souto Espiñeira, E. and Dominis Prester, D. and Donini, A. and Dorner, D. and Doro, M. and Elsaesser, D. and Fallah Ramazani, V. and Fattorini, A. and Ferrara, G. and Foffano, L. and Fonseca, M. V. and Font, L. and Fruck, C. and Fukami, S. and García López, R. J. and Garczarczyk, M. and Gasparyan, S. and Gaug, M. and Giglietto, N. and Giordano, F. and Gliwny, P. and Godinović, N. and Green, D. and Hadasch, D. and Hahn, A. and Herrera, J. and Hoang, J. and Hrupec, D. and Hütten, M. and Inada, T. and Inoue, S. and Ishio, K. and Iwamura, Y. and Jouvin, L. and Kajiwara, Y. and Karjalainen, M. and Kerszberg, D. and Kobayashi, Y. and Kubo, H. and Kushida, J. and Lamastra, A. and Lelas, D. and Leone, F. and Lindfors, E. and Lombardi, S. and Longo, F. and López, M. and López-Coto, R. and López-Oramas, A. and Loporchio, S. and Machado de Oliveira Fraga, B. and Maggio, C. and Majumdar, P. and Makariev, M. and Mallamaci, M. and Maneva, G. and Manganaro, M. and Mannheim, K. and Maraschi, L. and Mariotti, M. and Martínez, M. and Mazin, D. and Mender, S. and Mićanović, S. and Miceli, D. and Miener, T. and Minev, M. and Miranda, J. M. and Mirzoyan, R. and Molina, E. and Moralejo, A. and Morcuende, D. and Moreno, V. and Moretti, E. and Munar-Adrover, P. and Neustroev, V. and Nigro, C. and Nilsson, K. and Ninci, D. and Nishijima, K. and Noda, K. and Nogués, L. and Nozaki, S. and Ohtani, Y. and Oka, T. and Otero-Santos, J. and Palatiello, M. and Paneque, D. and Paoletti, R. and Paredes, J. M. and Pavletić, L. and Peñil, P. and Peresano, M. and Persic, M. and Prada Moroni, P. G. and Prandini, E. and Puljak, I. and Rhode, W. and Ribó, M. and Rico, J. and Righi, C. and Rugliancich, A. and Saha, L. and Sahakyan, N. and Saito, T. and Sakurai, S. and Satalecka, K. and Schleicher, B. and Schmidt, K. and Schweizer, T. and Sitarek, J. and Šnidarić, I. and Sobczynska, D. and Spolon, A. and Stamerra, A. and Strom, D. and Strzys, M. and Suda, Y. and Surić, T. and Takahashi, M. and Tavecchio, F. and Temnikov, P. and Terzić, T. and Teshima, M. and Torres-Albà, N. and Tosti, L. and van Scherpenberg, J. and Vanzo, G. and Vazquez Acosta, M. and Ventura, S. and Verguilov, V. and Vigorito, C. F. and Vitale, V. and Vovk, I. and Will, M. and Zarić, D. and Nievas-Rosillo, M. and Arcaro, C. and D’ Ammando, F. and de Palma, F. and Hodges, M. and Hovatta, T. and Kiehlmann, S. and Max-Moerbeck, W. and Readhead, A. C. S. and Reeves, R. and Takalo, L. and Reinthal, R. and Jormanainen, J. and Wierda, F. and Wagner, S. M. and Berdyugin, A. and Nabizadeh, A. and Talebpour Sheshvan, N. and Oksanen, A. and Bachev, R. and Strigachev, A. and Kehusmaa, P. (2020) Testing two-component models on very high-energy gamma-ray-emitting BL Lac objects. Astronomy and Astrophysics, 640 . Art. No. A132. ISSN 0004-6361.

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Context. It has become evident that one-zone synchrotron self-Compton models are not always adequate for very high-energy (VHE) gamma-ray-emitting blazars. While two-component models perform better, they are difficult to constrain due to the large number of free parameters. Aims. In this work, we make a first attempt at taking into account the observational constraints from very long baseline interferometry (VLBI) data, long-term light curves (radio, optical, and X-rays), and optical polarisation to limit the parameter space for a two-component model and test whether or not it can still reproduce the observed spectral energy distribution (SED) of the blazars. Methods. We selected five TeV BL Lac objects based on the availability of VHE gamma-ray and optical polarisation data. We collected constraints for the jet parameters from VLBI observations. We evaluated the contributions of the two components to the optical flux by means of decomposition of long-term radio and optical light curves as well as modelling of the optical polarisation variability of the objects. We selected eight epochs for these five objects based on the variability observed at VHE gamma rays, for which we constructed the SEDs that we then modelled with a two-component model. Results. We found parameter sets which can reproduce the broadband SED of the sources in the framework of two-component models considering all available observational constraints from VLBI observations. Moreover, the constraints obtained from the long-term behaviour of the sources in the lower energy bands could be used to determine the region where the emission in each band originates. Finally, we attempt to use optical polarisation data to shed new light on the behaviour of the two components in the optical band. Our observationally constrained two-component model allows explanation of the entire SED from radio to VHE with two co-located emission regions.

Item Type:Article
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URLURL TypeDescription Paper
Acciari, V. A.0000-0001-8991-7744
Readhead, A. C. S.0000-0001-9152-961X
Additional Information:© 2020 ESO. Article published by EDP Sciences. Received 25 February 2020; Accepted 8 June 2020; Published online 28 August 2020. We would like to thank the anonymous reviewer whose comments have helped us improving this manuscript. VFR and EL were supported by Academy of Finland projects 317636 and 320045. We would like to thank the Instituto de Astrofísica de Canarias for the excellent working conditions at the Observatorio del Roque de los Muchachos in La Palma. The financial support of the German BMBF and MPG; the Italian INFN and INAF; the Swiss National Fund SNF; the ERDF under the Spanish MINECO (FPA2017-87859-P, FPA2017-85668-P, FPA2017-82729-C6-2-R, FPA2017-82729-C6-6-R, FPA2017-82729-C6-5-R, AYA2015-71042-P, AYA2016-76012-C3-1-P, ESP2017-87055-C2-2-P, FPA2017-90566-REDC); the Indian Department of Atomic Energy; the Japanese ICRR, the University of Tokyo, JSPS, and MEXT; the Bulgarian Ministry of Education and Science, National RI Roadmap Project DO1-268/16.12.2019 and the Academy of Finland grant nr. 320045 is gratefully acknowledged. This work was also supported by the Spanish Centro de Excelencia “Severo Ochoa” SEV-2016-0588 and SEV-2015-0548, the Unidad de Excelencia “María de Maeztu” MDM-2014-0369 and the “la Caixa” Foundation (fellowship LCF/BQ/PI18/11630012), by the Croatian Science Foundation (HrZZ) Project IP-2016-06-9782 and the University of Rijeka Project, by the DFG Collaborative Research Centers SFB823/C4 and SFB876/C3, the Polish National Research Centre grant UMO-2016/22/M/ST9/00382 and by the Brazilian MCTIC, CNPq and FAPERJ. The Fermi-LAT Collaboration acknowledges generous ongoing support from a number of agencies and institutes that have supported both the development and the operation of the LAT as well as scientific data analysis. These include the National Aeronautics and Space Administration and the Department of Energy in the United States, the Commissariat à l’Energie Atomique and the Centre National de la Recherche Scientifique/Institut National de Physique Nucléaire et de Physique des Particules in France, the Agenzia Spaziale Italiana and the Istituto Nazionale di Fisica Nucleare in Italy, the Ministry of Education, Culture, Sports, Science and Technology (MEXT), High Energy Accelerator Research Organization (KEK) and Japan Aerospace Exploration Agency (JAXA) in Japan, and the K. A. Wallenberg Foundation, the Swedish Research Council and the Swedish National Space Board in Sweden. Additional support for science analysis during the operations phase is gratefully acknowledged from the Istituto Nazionale di Astrofisica in Italy and the Centre National d’Études Spatiales in France. This work performed in part under DOE Contract DE-AC02-76SF00515. Part of this work is based on observations made with the Nordic Optical Telescope, operated by the Nordic Optical Telescope Scientific Association at the Observatorio del Roque de los Muchachos, La Palma, Spain, of the Instituto de Astrofisica de Canarias. We acknowledge the support from the Bulgarian NSF through grants DN 18-1220 13/2017, DN 18-10/2017, KP-06-H28/3 (2018) and KP-06-PN38/1 (2019). This research has made use of data from the OVRO 40-m monitoring program which is supported in part by NASA grants NNX08AW31G, NNX11A043G, and NNX14AQ89G and NSF grants AST-0808050 and AST-1109911. This research has made use of data from the MOJAVE database that is maintained by the MOJAVE team (Lister et al. 2019). Part of this work is based on archival data, software, or online services provided by the Space Science Data Centre – ASI. This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC and the High Energy Astrophysics Division of the Smithsonian Astrophysical Observatory.
Group:Astronomy Department
Funding AgencyGrant Number
Academy of Finland317636
Academy of Finland320045
Bundesministerium für Bildung und Forschung (BMBF)UNSPECIFIED
Istituto Nazionale di Fisica Nucleare (INFN)UNSPECIFIED
Istituto Nazionale di Astrofisica (INAF)UNSPECIFIED
Swiss National Fund (SNF)UNSPECIFIED
European Regional Development FundUNSPECIFIED
Ministerio de Economía, Industria y Competitividad (MINECO)FPA2017-87859-P
Ministerio de Economía, Industria y Competitividad (MINECO)FPA2017-85668-P
Ministerio de Economía, Industria y Competitividad (MINECO)FPA2017-82729-C6-2-R
Ministerio de Economía, Industria y Competitividad (MINECO)FPA2017-82729-C6-6-R
Ministerio de Economía, Industria y Competitividad (MINECO)FPA2017-82729-C6-5-R
Ministerio de Economía, Industria y Competitividad (MINECO)AYA2015-71042-P
Ministerio de Economía, Industria y Competitividad (MINECO)AYA2016-76012-C3-1-P
Ministerio de Economía, Industria y Competitividad (MINECO)ESP2017-87055-C2-2-P
Ministerio de Economía, Industria y Competitividad (MINECO)FPA2017-90566-REDC
Department of Atomic Energy (India)UNSPECIFIED
Institute for Cosmic Ray ResearchUNSPECIFIED
University of TokyoUNSPECIFIED
Japan Society for the Promotion of Science (JSPS)UNSPECIFIED
Ministry of Education, Culture, Sports, Science and Technology (MEXT)UNSPECIFIED
Ministry of Education and Science (Bulgaria)DO1-268/16.12.2019
Centro de Excelencia Severo OchoaSEV-2016-0588
Centro de Excelencia Severo OchoaSEV-2015-0548
Ministerio de Economía, Industria y Competitividad (MINECO)MDM-2014-0369
la Caixa FoundationLCF/BQ/PI18/11630012
Croatian Science FoundationIP-2016-06-9782
University of Rijeka13.
Deutsche Forschungsgemeinschaft (DFG)SFB823/C4
Deutsche Forschungsgemeinschaft (DFG)SFB876/C3
National Science Centre (Poland)UMO-2016/22/M/ST9/00382
Ministério da Ciência, Tecnologia, Inovações e Comunicações (MCTIC)UNSPECIFIED
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)UNSPECIFIED
Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ)UNSPECIFIED
Department of Energy (DOE)DE-AC02-76SF00515
Ministry of Education and Science (Bulgaria)DN 18-1220 13/2017
Ministry of Education and Science (Bulgaria)DN 18-10/2017
Ministry of Education and Science (Bulgaria)KP-06-H28/3
Ministry of Education and Science (Bulgaria)KP-06-PN38/1
Subject Keywords:galaxies: active – galaxies: jets – BL Lacertae objects: general – astronomical databases: miscellaneous – radiation mechanisms: non-thermal – gamma rays: galaxies
Record Number:CaltechAUTHORS:20200901-100548058
Persistent URL:
Official Citation:Testing two-component models on very high-energy gamma-ray-emitting BL Lac objects. MAGIC Collaboration, V. A. Acciari, S. Ansoldi, L. A. Antonelli, A. Arbet Engels, D. Baack, A. Babić, B. Banerjee, U. Barres de Almeida, J. A. Barrio, J. Becerra González, W. Bednarek, L. Bellizzi, E. Bernardini, A. Berti, J. Besenrieder, W. Bhattacharyya, C. Bigongiari, A. Biland, O. Blanch, G. Bonnoli, Ž. Bošnjak, G. Busetto, R. Carosi, G. Ceribella, M. Cerruti, Y. Chai, A. Chilingarian, S. Cikota, S. M. Colak, U. Colin, E. Colombo, J. L. Contreras, J. Cortina, S. Covino, G. D’Amico, V. D’Elia, P. Da Vela, F. Dazzi, A. De Angelis, B. De Lotto, M. Delfino, J. Delgado, D. Depaoli, F. Di Pierro, L. Di Venere, E. Do Souto Espiñeira, D. Dominis Prester, A. Donini, D. Dorner, M. Doro, D. Elsaesser, V. Fallah Ramazani, A. Fattorini, G. Ferrara, L. Foffano, M. V. Fonseca, L. Font, C. Fruck, S. Fukami, R. J. García López, M. Garczarczyk, S. Gasparyan, M. Gaug, N. Giglietto, F. Giordano, P. Gliwny, N. Godinović, D. Green, D. Hadasch, A. Hahn, J. Herrera, J. Hoang, D. Hrupec, M. Hütten, T. Inada, S. Inoue, K. Ishio, Y. Iwamura, L. Jouvin, Y. Kajiwara, M. Karjalainen, D. Kerszberg, Y. Kobayashi, H. Kubo, J. Kushida, A. Lamastra, D. Lelas, F. Leone, E. Lindfors, S. Lombardi, F. Longo, M. López, R. López-Coto, A. López-Oramas, S. Loporchio, B. Machado de Oliveira Fraga, C. Maggio, P. Majumdar, M. Makariev, M. Mallamaci, G. Maneva, M. Manganaro, K. Mannheim, L. Maraschi, M. Mariotti, M. Martínez, D. Mazin, S. Mender, S. Mićanović, D. Miceli, T. Miener, M. Minev, J. M. Miranda, R. Mirzoyan, E. Molina, A. Moralejo, D. Morcuende, V. Moreno, E. Moretti, P. Munar-Adrover, V. Neustroev, C. Nigro, K. Nilsson, D. Ninci, K. Nishijima, K. Noda, L. Nogués, S. Nozaki, Y. Ohtani, T. Oka, J. Otero-Santos, M. Palatiello, D. Paneque, R. Paoletti, J. M. Paredes, L. Pavletić, P. Peñil, M. Peresano, M. Persic, P. G. Prada Moroni, E. Prandini, I. Puljak, W. Rhode, M. Ribó, J. Rico, C. Righi, A. Rugliancich, L. Saha, N. Sahakyan, T. Saito, S. Sakurai, K. Satalecka, B. Schleicher, K. Schmidt, T. Schweizer, J. Sitarek, I. Šnidarić, D. Sobczynska, A. Spolon, A. Stamerra, D. Strom, M. Strzys, Y. Suda, T. Surić, M. Takahashi, F. Tavecchio, P. Temnikov, T. Terzić, M. Teshima, N. Torres-Albà, L. Tosti, J. van Scherpenberg, G. Vanzo, M. Vazquez Acosta, S. Ventura, V. Verguilov, C. F. Vigorito, V. Vitale, I. Vovk, M. Will, D. Zarić, M. Nievas-Rosillo, C. Arcaro, F. D’ Ammando, F. de Palma, M. Hodges, T. Hovatta, S. Kiehlmann, W. Max-Moerbeck, A. C. S. Readhead, R. Reeves, L. Takalo, R. Reinthal, J. Jormanainen, F. Wierda, S. M. Wagner, A. Berdyugin, A. Nabizadeh, N. Talebpour Sheshvan, A. Oksanen, R. Bachev, A. Strigachev and P. Kehusmaa. A&A, 640 (2020) A132; DOI:
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ID Code:105198
Deposited By: Tony Diaz
Deposited On:09 Sep 2020 19:41
Last Modified:09 Sep 2020 19:41

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