Refereed journal article or data article (A1)

Multiwavelength Observations of the Blazar VER J0521+211 during an Elevated TeV Gamma-Ray State




List of Authors: Adams CB, Batista P, Benbow W, Brill A, Brose R, Buckley JH, Capasso M, Christiansen JL, Errando M, Feng Q, Finley JP, Foote GM, Fortson L, Furniss A, Gallagher G, Gent A, Giuri C, Hanlon WF, Hanna D, Hassan T, Hervet O, Holder J, Hona B, Hughes G, Humensky TB, Jin W, Kaaret P, Kertzman M, Kieda D, Kleiner TK, Krennrich F, Kumar S, Lang MJ, Lundy M, Maier G, Millis J, Moriarty P, Mukherjee R, Nievas-Rosillo M, Ong RA, Otte AN, Patel S, Patel SR, Pfrang K, Pohl M, Prado RR, Pueschel E, Quinn J, Ragan K, Reynolds PT, Ribeiro D, Roache E, Ryan JL, Sadeh I, Santander M, Sembroski GH, Shang R, Stevenson B, Tucci JV, Vassiliev VV, Wakely SP, Weinstein A, Wells RM, Williams DA, Williamson TJ, Acciari VA, Aniello T, Ansoldi S, Antonelli LA, Engels AA, Arcaro C, Artero M, Asano K, Baack D, Babic A, Baquero A, de Almeida UB, Barrio JA, Batkovic I, Gonzalez JB, Bednarek W, Bernardini E, Bernardos M, Berti A, Besenrieder J, Bhattacharyya W, Bigongiari C, Biland A, Blanch O, Bokenkamp H, Bonnoli G, Bosnjak Z, Burelli I, Busetto G, Carosi R, Ceribella G, Cerruti M, Chai Y, Chilingarian A, Cikota S, Colombo E, Contreras JL, Cortina J, Covino S, D'Amico G, D'Elia V, Da Vela P, Dazzi F, De Angelis A, De Lotto B, Del Popolo A, Delfino M, Delgado J, Mendez CD, Depaoli D, Di Pierro F, Di Venere L, Espineira ED, Prester DD, Donini A, Dorner D, Doro M, Elsaesser D, Ramazani VF, Farina L, Fattorini A, Font L, Fruck C, Fukami S, Fukazawa Y, Lopez RJG, Garczarczyk M, Gasparyan S, Gaug M, Giglietto N, Giordano F, Gliwny P, Godinovic N, Green JG, Green D, Hadasch D, Hahn A, Hassan T, Heckmann L, Herrera J, Hrupec D, Hutten M, Inada T, Iotov R, Ishio K, Iwamura Y, Martinez IJ, Jormanainen J, Jouvin L, Kerszberg D, Kobayashi Y, Kubo H, Kushida J, Lamastra A, Lelas D, Leone F, Lindfors E, Linhoff L, Lombardi S, Longo F, Lopez-Coto R, Lopez-Moya M, Lopez-Oramas A, Loporchio S, Lorini A, Fraga BMD, Maggio C, Majumdar P, Makariev M, Maneva G, Manganaro M, Mannheim K, Mariotti M, Martinez M, Aguilar AM, Mazin D, Menchiari S, Mender S, Micanovic S, Miceli D, Miener T, Miranda JM, Mirzoyan R, Molina E, Mondal HA, Moralejo A, Morcuende D, Moreno V, Nakamori T, Nanci C, Nava L, Neustroev V, Rosillo MN, Nigro C, Nilsson K, Nishijima K, Noda K, Nozaki S, Ohtani Y, Oka T, Otero-Santos J, Paiano S, Palatiello M, Paneque D, Paoletti R, Paredes JM, Pavletic L, Penil P, Persic M, Pihet M, Moroni PGP, Prandini E, Priyadarshi C, Puljak I, Rhode W, Ribo M, Rico J, Righi C, Rugliancich A, Sahakyan N, Saito T, Sakurai S, Satalecka K, Saturni FG, Schleicher B, Schmidt K, Schmuckermaier F, Schubert JL, Schweizer T, Sitarek J, Snidaric I, Sobczynska D, Spolon A, Stamerra A, Striskovic J, Strom D, Strzys M, Suda Y, Suric T, Takahashi M, Takeishi R, Tavecchio F, Temnikov P, Terzic T, Teshima M, Tosti L, Truzzi S, Tutone A, Ubach S, van Scherpenberg J, Vanzo G, Acosta MV, Ventura S, Verguilov V, Viale I, Vigorito CF, Vitale V, Vovk I, Will M, Wunderlich C, Yamamoto T, Zaric D; VERITAS Collaboration (VERITAS Collaboration) ; MAGIC Collaboration (MAGIC Collaboration)

Publisher: IOP Publishing Ltd

Publication year: 2022

Journal: Astrophysical Journal

Journal name in source: ASTROPHYSICAL JOURNAL

Journal acronym: ASTROPHYS J

Volume number: 932

Issue number: 2

Number of pages: 17

ISSN: 0004-637X

DOI: http://dx.doi.org/10.3847/1538-4357/ac6dd9

URL: https://iopscience.iop.org/article/10.3847/1538-4357/ac6dd9

Self-archived copy’s web address: https://research.utu.fi/converis/portal/detail/Publication/175934559


Abstract
We report on a long-lasting, elevated gamma-ray flux state from VER J0521+211 observed by VERITAS, MAGIC, and Fermi-LAT in 2013 and 2014. The peak integral flux above 200 GeV measured with the nightly binned light curve is (8.8 +/- 0.4) x 10(-7) photons m(-2) s(-1), or similar to 37% of the Crab Nebula flux. Multiwavelength observations from X-ray, UV, and optical instruments are also presented. A moderate correlation between the X-ray and TeV gamma-ray fluxes was observed, and the X-ray spectrum appeared harder when the flux was higher. Using the gamma-ray spectrum and four models of the extragalactic background light (EBL), a conservative 95% confidence upper limit on the redshift of the source was found to be z <= 0.31. Unlike the gamma-ray and X-ray bands, the optical flux did not increase significantly during the studied period compared to the archival low-state flux. The spectral variability from optical to X-ray bands suggests that the synchrotron peak of the spectral energy distribution (SED) may become broader during flaring states, which can be adequately described with a one-zone synchrotron self-Compton model varying the high-energy end of the underlying particle spectrum. The synchrotron peak frequency of the SED and the radio morphology of the jet from the MOJAVE program are consistent with the source being an intermediate-frequency-peaked BL Lac object.

Downloadable publication

This is an electronic reprint of the original article.
This reprint may differ from the original in pagination and typographic detail. Please cite the original version.




Last updated on 2022-15-08 at 09:57