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arXiv · 1911.06680

New hard-TeV extreme blazars detected with the MAGIC telescopes

MAGIC Collaboration·V. A. Acciari·S. Ansoldi·L. A. Antonelli·A. Arbet Engels·K. Asano·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. Chilingaryan·S. Cikota·S. M. Colak·U. Colin·E. Colombo·J. L. Contreras·J. Cortina·S. Covino·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·D. Fidalgo·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·N. Godinović·D. Green·D. Guberman·D. Hadasch·A. Hahn·J. Herrera·J. Hoang·D. Hrupec·M. Hütten·T. Inada·S. Inoue·K. Ishio·Y. Iwamura·L. Jouvin·D. Kerszberg·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
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Abstract

Extreme high-frequency peaked BL Lac objects (EHBLs) are blazars which exhibit extremely energetic synchrotron emission. They also feature non-thermal gamma-ray emission whose peak lies in the very high-energy (VHE, E > 100 GeV) range, and in some sources exceeds 1TeV: this is the case of hard-TeV EHBLs such as 1ES 0229+200. With the aim of increasing the EHBL population, ten targets were observed with the MAGIC telescopes from 2010 to 2017, for a total of 262 h of good quality data. The data were complemented by coordinated Swift observations. The X-ray data analysis confirms that all the sources but two are EHBLs. The sources show only a modest variability and a harder-when-brighter behavior, typical for this class of objects. At VHE gamma rays, three new sources were detected and a hint of signal was found for another new source. In each case the intrinsic spectrum is compatible with the hypothesis of a hard-TeV nature of these EHBLs. The broadband spectral energy distributions (SEDs) of all sources are built and modeled in the framework of a single-zone purely leptonic model. The VHE gamma-ray detected sources were also interpreted with a spine-layer and a proton synchrotron models. The three models provide a good description of the SEDs. However, the resulting parameters differ substantially in the three scenarios, in particular the magnetization parameter. This work presents a first mini-catalog of VHE gamma-ray and multi-wavelength observations of EHBLs.

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MAGIC Collaboration, V. A. Acciari, S. Ansoldi, L. A. Antonelli, A. Arbet Engels, K. Asano, 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. Chilingaryan, S. Cikota, S. M. Colak, U. Colin, E. Colombo, J. L. Contreras, J. Cortina, S. Covino, 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, D. Fidalgo, 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, N. Godinović, D. Green, D. Guberman, D. Hadasch, A. Hahn, J. Herrera, J. Hoang, D. Hrupec, M. Hütten, T. Inada, S. Inoue, K. Ishio, Y. Iwamura, L. Jouvin, D. Kerszberg, 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. 2020-08-20. New hard-TeV extreme blazars detected with the MAGIC telescopes. https://doi.org/10.3847/1538-4365%2Fab5b98

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