Extreme blazars under the eyes of MAGIC

Discussion timeslot (ZOOM-Meeting): 13. July 2021 - 18:00
ZOOM-Meeting URL: https://desy.zoom.us/j/98542982538
ZOOM-Meeting ID: 98542982538
ZOOM-Meeting Passcode: ICRC2021
Corresponding Session: https://icrc2021-venue.desy.de/channel/48-Modelling-AGN039s-spectral-energy-distribution-GAD-GAI-MM/77
Live-Stream URL: https://icrc2021-venue.desy.de/livestream/Discussion-04/5

Abstract:
Extreme high-frequency-peaked BL Lac objects (EHBLs) are the most energetic persistent sources in the universe. This contribution reports on long-term observing campaigns of tens of EHBLs that have been organized by the MAGIC collaboration to enlarge their population at VHE and understand the origin of their extreme properies. EHBLs are characterized by a spectral energy distribution (SED) featuring a synchrotron peak energy above 1 keV. Several EHBLs display a hard spectral index at very high energies (VHE, E larger 100 GeV), suggesting a gamma-ray SED component peaking significantly above 1 TeV. Such extreme properties are challenging current standard emission and acceleration mechanisms. Recent studies have also unveiled intriguing disparities in the temporal characteristics of EHBLs. Some sources seem to display a persistent EHBL behaviour, while others belong to the EHBL family only temporarily.rnWe will focus on the recent results of the first hard-TeV EHBL catalog. The MAGIC observations are accompanied by an extensive multi-wavelength coverage to obtain an optimal determination of the SED. This allow us to investigate leptonic and hadronic scenarios for the emission. We will also present the recent detection of the EHBL 1RXS0812.0+0237 in the VHE band by MAGIC. Finally, we will discuss a broad multi-wavelength campaign on the BL Lac type object 1ES2344+514, which showed intermittent EHBL characteristics in August 2016.'

Authors: Axel Arbet-Engels
Co-Authors: Cornelia Arcaro | Katsuaki Asano | Josefa Becerra González | Giacomo Bonnoli | Matteo Cerruti | Filippo D'Ammando | Paolo Da Vela | Daniela Dorner | Vandad Fallah Ramazani | Luca Foffano | Jenni Jormanainen | Marina Manganaro | Elisa Prandini | Fabrizio Tavecchio | Sofia Ventura | for the MAGIC and FACT Collaborations
Collaboration: MAGICFACT

Indico-ID: 1153
Proceeding URL: https://pos.sissa.it/395/865