J/A+A/694/A195 Mrk 421 multiwavelength variability (Abe+, 2025)
Characterization of Markarian 421 during its most violent year:
Multiwavelength variability and correlations.
Abe K., Abe S., Abhir J., Abhishek A., Acciari V.A., Aguasca-Cabot A.,
Agudo I., Aniello T., Ansoldi S., Antonelli L.A., Arbet Engels A.,
Arcaro C., Asano K., Baack D., Babic A., Barres de Almeida U., Barrio J.A.,
Batkovic I., Bautista A., Baxter J., Becerra Gonzalez J., Bednarek W.,
Bernardini E., Bernete J., Berti A., Besenrieder J., Bigongiari C.,
Biland A., Blanch O., Bonnoli G., Bosnjak Z., Bronzini E., Burelli I.,
Campoy-Ordaz A., Carosi R., Carretero-Castrillo M., Castro-Tirado A.J.,
Cerasole D., Ceribella G., Chai Y., Cifuentes A., Colombo E.,
Contreras J.L., Cortina J., Covino S., D'Amico G., D'Ammando F., D'Elia V.,
Da Vela P., Dazzi F., De Angelis A., De Lotto B., de Menezes R., Delfino M.,
Delgado J., Delgado Mendez C., Di Pierro F., Di Tria R., Di Venere L.,
Dominis Prester D., Donini A., Dorner D., Doro M., Eisenberger L.,
Elsaesser D., Escudero J., Farina L., Fattorini A., Foffano L., Font L.,
Frose S., Fukami S., Fukazawa Y., Garcia Lopez R.J., Garczarczyk M.,
Gasparyan S., Gaug M., Giesbrecht Paiva J.G., Giglietto N., Giordano F.,
Gliwny P., Godinovic N., Gradetzke T., Grau R., Green D., Green J.G.,
Gunther P., Hadasch D., Hahn A., Hassan T., Heckmann L.,
Herrera Llorente J., Hrupec D., Imazawa R., Ishio K., Jimenez Martinez I.,
Jormanainen J., Kankkunen S., Kayanoki T., Kerszberg D., Kluge G.W.,
Kouch P.M., Kubo H., Kushida J., Lainez M., Lamastra A., Leone F.,
Lindfors E., Lombardi S., Longo F., Lopez-Coto R., Lopez-Moya M.,
Lopez-Oramas A., Loporchio S., Lorini A., Majumdar P., Makariev M.,
Maneva G., Manganaro M., Mangano S., Mannheim K., Mariotti M., Martinez M.,
Martinez-Chicharro M., Mas-Aguilar A., Mazin D., Menchiari S., Mender S.,
Miceli D., Miener T., Miranda J.M., Mirzoyan R., Molero Gonzalez M.,
Molina E., Mondal H.A., Moralejo A., Morcuende D., Nakamori T., Nanci C.,
Neustroev V., Nickel L., Nigro C., Nikolic L., Nilsson K., Nishijima K.,
Njoh Ekoume T., Noda K., Nozaki S., Okumura A., Otero-Santos J., Paiano S.,
Paneque D., Paoletti R., Paredes J.M., Peresano M., Persic M., Pihet M.,
Pirola G., Podobnik F., Prada Moroni P.G., Prandini E., Principe G.,
Rhode W., Ribo M., Rico J., Righi C., Sahakyan N., Saito T., Saturni F.G.,
Schmidt K., Schmuckermaier F., Schubert J.L., Schweizer T., Sciaccaluga A.,
Silvestri G., Sitarek J., Sobczynska D., Stamerra A., Striskovic J.,
Strom D., Suda Y., Tajima H., Takahashi M., Takeishi R., Tavecchio F.,
Temnikov P., Terauchi K., Terzic T., Teshima M., Truzzi S., Tutone A.,
Ubach S., van Scherpenberg J., Ventura S., Verna G., Viale I.,
Vigorito C.F., Vitale V., Vovk I., Walter R., Wersig F., Will M.,
Yamamoto T., Jorstad S.G., Marscher A.P., Perri M., Leto C., Verrecchia F.,
Aller M., Max-Moerbeck W., Readhead A.C.S., Lahteenmaki A., Tornikoski M.,
Gurwell M.A., Wehrle A.E.
<Astron. Astrophys. 694, A195 (2025)>
=2025A&A...694A.195A 2025A&A...694A.195A (SIMBAD/NED BibCode)
ADC_Keywords: BL Lac objects ; Radio sources ; X-ray sources ; Gamma rays
Keywords: galaxies: active - BL Lacertae objects: individual: Mrk 421
Abstract:
Mrk 421 was in its most active state around early 2010, which led to
the highest TeV gamma-ray flux ever recorded from any active galactic
nuclei (AGN). We aim to characterize the multiwavelength behavior
during this exceptional year for Mrk 421, and evaluate whether it is
consistent with the picture derived with data from other less
exceptional years. We investigated the period from November 5, 2009,
(MJD 55140) until July 3, 2010, (MJD 55380) with extensive coverage
from very-high-energy (VHE; E>100GeV) gamma rays to radio with MAGIC,
VERITAS, Fermi-LAT, RXTE, Swift, GASP-WEBT, VLBA, and a variety of
additional optical and radio telescopes. We characterized the
variability by deriving fractional variabilities as well as power
spectral densities (PSDs). In addition, we investigated images of the
jet taken with VLBA and the correlation behavior among different
energy bands. Mrk 421 was in widely different states of activity
throughout the campaign, ranging from a low-emission state to its
highest VHE flux ever recorded. We find the strongest variability in
X-rays and VHE gamma rays, and PSDs compatible with power-law
functions with indices around 1.5. We observe strong correlations
between X-rays and VHE gamma rays at zero time lag with varying
characteristics depending on the exact energy band. We also report a
marginally significant (∼3σ) positive correlation between
high-energy (HE; E>100MeV) gamma rays and the ultraviolet band. We
detected marginally significant (∼3σ) correlations between the
HE and VHE gamma rays, and between HE gamma rays and the X-ray, that
disappear when the large flare in February 2010 is excluded from the
correlation study, hence indicating the exceptionality of this flaring
event in comparison with the rest of the campaign. The 2010 violent
activity of Mrk421 also yielded the first ejection of features in the
VLBA images of the jet of Mrk 421. Yet the large uncertainties in the
ejection times of these unprecedented radio features prevent us from
firmly associating them to the specific flares recorded during the
2010 campaign. We also show that the collected multi-instrument data
are consistent with a scenario where the emission is dominated by two
regions, a compact and extended zone, which could be considered as a
simplified implementation of an energy-stratified jet as suggested by
recent IXPE observations.
Description:
In this work, we present a detailed data set covering the most active
year of the blazar Mrk421. We focus on investigating the
multiwavelength variability and correlation patterns, as well as radio
data collected by the VLBA. This Readme describes the data files
published together with the paper. The data from figure 1 are made
available.
Objects:
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RA (2000) DE Designation(s)
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11 04 27.31 +38 12 31.8 Mrk 421 = SWIFT J1104.5+3813
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
fig1.dat 88 2318 Multiwavelength light curves of Fig. 1
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See also:
J/A+A/576/A126 : The 2009 multiwavelength campaign on Mrk421 (Aleksic+, 2015)
J/A+A/578/A22 : Mrk421 in March 2010 (Aleksic+, 2015)
J/A+A/593/A91 : Mrk 421 multi-wavelength variability, 2007-2009 (Ahnen+, 2016)
J/ApJS/248/29 : Simultaneous X-ray & gamma obs. of Mrk421 in 2013
(Acciari+, 2020)
J/A+A/655/A89 : Mrk421 multi-instrument observations in 2017 (Acciari+, 2021)
J/A+A/684/A127 : Mrk 421 multiwavelength light curves (Abe+, 2024)
Byte-by-byte Description of file: fig1.dat
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Bytes Format Units Label Explanations
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1- 10 F10.4 d MJD Modified Julian date center
13- 21 E9.2 --- Flux/pol Flux or polarization degree/angle
24- 31 E8.2 --- e_Flux/pol Flux uncertainty or polarization degree/angle
34- 41 A8 --- Energy Energy range or Filter
46- 55 A10 --- Inst Instrument
58- 69 A12 --- Unit Units
70- 88 A19 --- Param Parameter (Flux, Polarization Degree or
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Acknowledgements:
Felix Schmuckermaier, fschmuck(at)mpp.mpg.de
(End) Patricia Vannier [CDS] 21-Jan-2025