PoS - Proceedings of Science
Volume 395 - 37th International Cosmic Ray Conference (ICRC2021) - GAI - Gamma Ray Indirect
Unveiling the complex correlation patterns in Mrk 421
A. Arbet-Engels*, D. Paneque, L. Heckmann,  The MAGIC Collaboration,  The FACT Collaboration,  The Fermi-LAT Collaboration, V.A. Acciari, S. Ansoldi, L.A. Antonelli, M. Artero, K. Asano, D. Baack, A. Babić, A. Baquero, U. Barres de Almeida, J.A. Barrio, I. Batković, J. Becerra González, W. Bednarek, L. Bellizzi, E. Bernardini, M.I. Bernardos, A. Berti, J. Besenrieder, W. Bhattacharyya, C. Bigongiari, A. Biland, O. Blanch, H. Bökenkamp, G. Bonnoli, Ž. Bošnjak, G. Busetto, R. Carosi, G. Ceribella, M. Cerruti, Y. Chai, A. Chilingarian, S. Cikota, S.M. Colak, 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, C. Delgado Mendez, 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, M.V. Fonseca, L. Font, C. Fruck, S. Fukami, Y. Fukazawa, R.J. García López, M. Garczarczyk, S. Gasparyan, M. Gaug, N. Giglietto, F. Giordano, P. Gliwny, N. Godinović, D. Green, J.G. Green, D. Hadasch, A. Hahn, J. Herrera, J. Hoang, D. Hrupec, M. Hütten, T. Inada, K. Ishio, Y. Iwamura, I. Jiménez Martínez, J. Jormanainen, L. Jouvin, M. Karjalainen, D. Kerszberg, Y. Kobayashi, H. Kubo, J. Kushida, A. Lamastra, D. Lelas, F. Leone, E. Lindfors, L. Linhoff, S. Lombardi, F. Longo, R. López-Coto, M. López-Moya, 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. Menchiari, S. Mender, S. Mićanović, D. Miceli, T. Miener, J.M. Miranda, R. Mirzoyan, E. Molina, A. Moralejo, D. Morcuende, V. Moreno, E. Moretti, T. Nakamori, L. Nava, V. Neustroev, C. Nigro, K. Nilsson, K. Nishijima, K. Noda, S. Nozaki, Y. Ohtani, T. Oka, J. Otero-Santos, S. Paiano, M. Palatiello, R. Paoletti, J.M. Paredes, L. Pavletić, P. Peñil, M. Persic, M. Pihet, P.G. Prada Moroni, E. Prandini, C. Priyadarshi, I. Puljak, W. Rhode, M. Ribó, J. Rico, C. Righi, A. Rugliancich, N. Sahakyan, T. Saito, S. Sakurai, K. Satalecka, F.G. Saturni, B. Schleicher, K. Schmidt, T. Schweizer, J. Sitarek, I. Šnidarić, D. Sobczyńska, A. Spolon, A. Stamerra, J. Strišković, D. Strom, M. Strzys, Y. Suda, T. Surić, M. Takahashi, R. Takeishi, F. Tavecchio, P. Temnikov, T. Terzić, M. Teshima, L. Tosti, S. Truzzi, A. Tutone, S. Ubach, J. van Scherpenberg, G. Vanzo, M. Vazquez Acosta, S. Ventura, V. Verguilov, C.F. Vigorito, V. Vitale, I. Vovk, M. Will, C. Wunderlich, T. Yamamoto, D. Zarić, M. Balbo, T. Bretz, J. Buss, L. Eisenberger, D. Hildebrand, R. Iotov, A. Kalenski, A. Mitchell, D. Neise, M. Noethe, A. Paravac, V. Sliusar, R. Walter, F. D'Ammando, D. Horan, A.Y. Lien, M. Balokovic, G.M. Madejski, M. Perri, F. Verrecchia, C. Leto, A. Lähteenmäki, M. Tornikoski, V. Ramakrishnan, E. Järvelä, R.J.C. Vera, M. Villata and C.M. Raiteriet al. (click to show)
Full text: pdf
Pre-published on: July 30, 2021
Published on:
Abstract
The blazar Mrk421 (redshift z=0.031) is one of the brightest and closest BL Lac type objects, making it an ideal target to probe blazar physics. We report on an extensive multi-wavelength observing campaign in 2017, during which the intra-band correlation patterns show some disparity and complex behaviours. Observations from several instruments are used to achieve an optimal temporal coverage from radio to TeV energies. In particular, four multi-hour NuSTAR observations organised simultaneously with MAGIC allow to obtain a precise measurement of the falling segments of the two spectral components. A detailed investigation of the very-high-energy (VHE; >100 GeV) versus X-ray flux correlation is performed, by binning the data into several sub-energy bands. A positively correlated variability is observed, but the correlation characteristics change substantially across the various bands probed. Furthermore, during the simultaneous MAGIC and NuSTAR observations a clear change of the Compton dominance is detected without a simultaneous change in the synchrotron regime, indicating "orphan gamma-ray activity". We also investigate an intriguing bright flare at VHE without a substantial flux increase in the X-rays. Within a leptonic scenario, this behaviour is best explained by the appearance of a second population of highly-energetic electrons spanning a narrow range of energies. Finally, our multi-wavelength correlation study also reveals an anti-correlation between the UV/optical and X-ray bands at a significance level above 3 sigma.
DOI: https://doi.org/10.22323/1.395.0834
How to cite

Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.

Open Access
Creative Commons LicenseCopyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.