J/ApJS/248/29ivo://CDS.VizieR/J/ApJS/248/29doi:10.26093/cds/vizier.22480029CDSAcciari V.A.Ansoldi S.Antonelli L.A.Engels A.A.Baack D.Babic A.,Banerjee B.Barres de Almeida U.Barrio J.A.Becerra Gonzalez J.,Bednarek W.Bellizzi L.K.Bernardini E.Berti A.Besenrieder J.,Bhattacharyya W.Bigongiari C.Biland A.Blanch O.Bonnoli G.,Bosnjak Z.Busetto G.Carosi R.Ceribella G.Cerruti M.Chai Y.,Chilingarian A.Cikota S.Colak S.M.Colin U.Colombo E.,Contreras J.L.Cortina J.Covino S.D'Elia V.Da Vela P.Dazzi F.,De Angelis A.De Lotto B.Del Puppo F.Delfino M.Delgado J.,Depaoli D.Di Pierro F.Di Venere L.Do Souto Espineira E.,Dominis Prester D.Donini A.Dorner D.Doro M.Elsaesser D.,Fallah Ramazani V.Fattorini A.Ferrara G.Foffano L.Fonseca M.V.,Font L.Fruck C.Fukami S.Garcia Lopez R.J.Garczarczyk M.,Gasparyan S.Gaug M.Giglietto N.Giordano F.Gliwny P.Godinovic N.,Green D.Hadasch D.Hahn A.Hassan T.Herrera J.Hoang J.Hrupec D.,Hutten M.Inada T.Inoue S.Ishio K.Iwamura Y.Jouvin L.Kajiwara Y.,Kerszberg D.Kobayashi Y.Kubo H.Kushida J.Lamastra A.Lelas D.,Leone F.Lindfors E.Lombardi S.Longo F.Lopez M.Lopez-Coto R.,Lopez-Oramas A.Loporchio S.Machado de Oliveira Fraga B.Maggio C.,Majumdar P.Makariev M.Mallamaci M.Maneva G.Manganaro M.,Mannheim K.Maraschi L.Mariotti M.Martinez M.Mazin D.Mender S.,Micanovic S.Miceli D.Miener T.Minev M.Miranda J.M.Mirzoyan R.,Molina E.Moralejo A.Morcuende D.Moreno V.Moretti E.,Munar-Adrover P.Neustroev V.Nigro C.Nilsson K.Ninci D.,Nishijima K.Noda K.Nogues L.Nozaki S.Ohtani Y.Oka T.,Otero-Santos J.Palatiello M.Paneque D.Paoletti R.Paredes J.M.,Pavletic L.Penil P.Peresano M.Persic M.Prada Moroni P.G.,Prandini E.Puljak I.Rhode W.Ribo M.Rico J.Righi C.,Rugliancich A.Saha L.Sahakyan N.Saito T.Sakurai S.Satalecka K.,Schleicher B.Schmidt K.Schweizer T.Sitarek J.Snidaric I.,Sobczynska D.Spolon A.Stamerra A.Strom D.Strzys M.Suda Y.,Suric T.Takahashi M.Tavecchio F.Temnikov P.Terzic T.Teshima M.,Torres-Alba N.Tosti L.van Scherpenberg J.Vanzo G.Vasquez Acosta M.,Ventura S.Verguilov V.Vigorito C.F.Vitale V.Vovk I.Will M.,Zaric D. (The MAGIC Collaboration)Petropoulou M.Finke J.,D'Ammando F.Balokovic M.Madejski G.Mori K.Puccetti S.Leto C.,Perri M.Verrecchia F.Villata M.Raiteri C.M.Agudo I.Bachev R.,Berdyugin A.Blinov D.A.Chanishvili R.Chen W.P.Chigladze R.,Damljanovic G.Eswaraiah C.Grishina T.S.Ibryamov S.Jordan B.,Jorstad S.G.Joshi M.Kopatskaya E.N.Kurtanidze O.M.Kurtanidze S.O.,Larionova E.G.Larionova L.V.Larionov V.M.Latev G.Lin H.C.,Marscher A.P.Mokrushina A.A.Morozova D.A.Nikolashvili M.G.Semkov E.,Smith P.S.Strigachev A.Troitskaya Y.V.Troitsky I.S.Vince O.,Barnes J.Guver T.Moody J.W.Sadun A.C.Hovatta T.Richards J.L.,Max-Moerbeck W.Readhead A.C.S.Lahteenmaki A.Tornikoski M.Tammi J.,Ramakrishnan V.Reinthal R.2026-08-03T07:24:45Z2021-02-19T11:38:15ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.fractive-galactic-nucleix-ray-sourcesgamma-ray-astronomypolarimetryvisible-astronomyradio-sourcesWe report on a multiband variability and correlation study of the TeV blazar Mrk 421 during an exceptional flaring activity observed from 2013 April 11 to 19. The study uses, among others, data from GLAST-AGILE Support Program (GASP) of the Whole Earth Blazar Telescope (WEBT), Swift, Nuclear Spectroscopic Telescope Array (NuSTAR), Fermi Large Area Telescope, Very Energetic Radiation Imaging Telescope Array System (VERITAS), and Major Atmospheric Gamma Imaging Cherenkov (MAGIC). The large blazar activity and the 43hr of simultaneous NuSTAR and MAGIC/VERITAS observations permitted variability studies on 15 minute time bins over three X-ray bands (3-7keV, 7-30keV, and 30-80keV) and three very-high-energy (VHE; >0.1TeV) gamma-ray bands (0.2-0.4TeV, 0.4-0.8TeV, and >0.8TeV). We detected substantial flux variations on multi-hour and sub-hour timescales in all of the X-ray and VHE gamma-ray bands. The characteristics of the sub-hour flux variations are essentially energy independent, while the multi-hour flux variations can have a strong dependence on the energy of the X-rays and the VHE gamma-rays. The three VHE bands and the three X-ray bands are positively correlated with no time lag, but the strength and characteristics of the correlation change substantially over time and across energy bands. Our findings favor multi-zone scenarios for explaining the achromatic/chromatic variability of the fast/slow components of the light curves, as well as the changes in the flux-flux correlation on day- long timescales. We interpret these results within a magnetic reconnection scenario, where the multi-hour flux variations are dominated by the combined emission from various plasmoids of different sizes and velocities, while the sub-hour flux variations are dominated by the emission from a single small plasmoid moving across the magnetic reconnection layer.2020ApJS..248...29Ahttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/248/29CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/545/A117 : Monitoring of Mrk 421 at 15 and 24 GHz (Lico+, 2012)J/A+A/559/A75 : 43GHz observation of the blazar Mrk 421 (Blasi+, 2013)J/A+A/573/A50 : Multiwavelength obs. of Mrk 501 in 2008 (Aleksic+, 2015)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/ApJ/831/102 : Swift and NuSTAR obs. of the BL Lac Mrk 421 (Kapanadze+, 2016)J/ApJS/222/6 : 4.5yr obs. of Mrk421 with ARGO-YBJ + Fermi (Bartoli+, 2016)J/ApJS/232/7 : 8yr R-band photopolarimetric data of Mrk421 (Fraija+, 2017)J/ApJ/851/33 : Multi-wavelength analysis of CGRaBS blazars (Paliya+, 2017)J/ApJ/858/68 : Mrk421 with Swift in selected epochs. II. (Kapanadze+, 2018)J/ApJ/874/43 : MOJAVE. XVII. Jet kinematics of AGNs (Lister+, 2019)J/ApJS/247/27 : Mrk 421 Swift obs. III. 2015 Dec-2018 Apr (Kapanadze+, 2020)J/ApJS/247/33 : The Fermi LAT fourth source catalog (4FGL) (Abdollahi+, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/248/29https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/248/29http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/248/29https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/248/29https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/248/29http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/248/29GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapGamma-rayX-rayOpticalRadiodefaultJ/ApJS/248/29/fig1fluxMultiwavelength fluxes for Mrk421 during the bright flaring activity in 2013 AprilrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMJDl? Modified Julian date, bin lowdtime.epochdoublenullableMJDcModified Julian date, bin centerdtime.epochdoubleMJDh? Modified Julian date, bin highdtime.epochdoublenullableFluxFlux with instrument in energy rangephot.flux.densitydoublee_FluxUncertainty in Fluxstat.error;phot.fluxdoubleInstInstrumentmeta.id;instrcharEnergyEnergy range / Filterinstr.bandpasscharx_FluxFlux units (erg/cm2/s, mJy or ph/cm2/s)meta.unit;phot.fluxcharJ/ApJS/248/29/fig1polPolarization data for Mrk421 during the bright flaring activity in 2013 AprilrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMJDModified Julian Date of observation (JD-2400000.5)dtime.epochdoublePol[0.89/9.62] Polarization degree%phys.polarizationfloate_Pol[0.015/0.6] Error in Pol%stat.errorfloatEVPA[-90.1/47.2] Electric vector position angledegpos.posAng;phys.polarizationfloate_EVPA[0.1/5.1] Error in EVPAdegstat.errorfloatInstInstrumentmeta.id;instrcharFiltEnergy range / Filter (R-band ; or 86GHz (1 occurrence for IRAM))instr.bandwidth;instr.filtercharJ/ApJS/248/29/fig2Light curves in various VHE and X-ray energy bands -- Data behind Figure 2recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMJDlModified Julian date, bin lowdtime.epochdoubleMJDcModified Julian date, bin centerdtime.epochdoubleMJDhModified Julian date, bin highdtime.epochdoubleFluxFlux with Instrument in Energy Range having Unitphot.flux.densitydoublee_FluxUncertainty in Fluxstat.error;phot.fluxdoubleInstInstrument (NuSTAR, MAGIC, VERITAS or Swift)meta.id;instrcharEnergyEnergy range / Filterinstr.bandpasscharx_FluxFlux units (erg/cm2/s or ph/cm2/s)meta.unit;phot.fluxcharJ/ApJS/248/29/fig3intFractional variability vs energy for the 9-day interval -- Data behind Figure 3recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintlogE[10.17/26.99] log Energy range centerlog(Hz)em.energyfloatlogdE[0.01/1.5] log Energy range halfwidthlog(Hz)em.energyfloatFvar[-0.02/1.06] Fractional variabilitysrc.var.indexdoublee_Fvar[0.0008/0.13] Uncertainty in Fvarstat.errordoubleLabelObservation labelmeta.id;obscharJ/ApJS/248/29/fig3ntNight-wise fractional variability vs energy -- Data behind Figure 3e_Fvar[0.002/0.12] Uncertainty in Fvarstat.errordoubleInstInstrument (NuStar or "VHE (MAGIC & VERITAS)")meta.id;instrcharDateObservation datetime.epoch;obsnullableMJDModified Julian Date (JD-2400000.5)dtime.epochintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintlogE[18.04/27] log Energy range centerlog(Hz)em.energyfloatlogdE[0.15/0.7] log Energy range halfwidthlog(Hz)em.energyfloatFvar[0.049/0.47] Fractional variabilitysrc.var.indexdoubleJ/ApJS/248/29/fig4Light curves from 2013 April 15 in three X-ray bands and three VHE gamma-ray bandsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTime[-3.2/9.8] Time in hours from MJD 56397htime.epochfloatdT[0.018/0.14] Time bin halfwidthhtime.intervalfloatFluxFlux with Instrument in Energy Range having Unitphot.flux.densitydoublee_FluxUncertainty in Fluxstat.error;phot.fluxdoubleInstInstrument (NuSTAR, MAGIC or VERITAS)meta.id;instrcharEnergyEnergy range / Filterinstr.bandpasscharx_FluxFlux units (erg/cm2/s or ph/cm2/s)meta.unit;phot.fluxcharJ/ApJS/248/29/fig5X-ray and VHE hardness (flux) ratios for several X-ray and VHE bands -- Data behind Fig 5recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTime[-2.45/8.5] Time in hours from MJD 56397htime.epochfloatdT[0.018/0.14] Time bin halfwidthhtime.intervalfloatRatio[0.18/1.3] Flux Ratiophot.flux;arith.ratiofloate_Ratio[0.009/0.3] Error in Ratiostat.error;arith.ratiofloatEnergyEnergy ranges of Ratioinstr.bandpasscharJ/ApJS/248/29/fig6VHE flux vs. X-ray flux in three X-ray and three VHE energy bands -- Data behind Figure 6recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMJDcModified Julian date, bin centerdtime.epochdoubleFluxX[3.8e-12/2.2e-09] Xray Flux, erg/cm2/smW.m**-2phot.flux;em.X-raydoublee_FluxX[1e-12/1.5e-10] Uncertainty in Xray FluxmW.m**-2stat.errordoubleFluxV[6.7e-12/1.3e-09] VHE fluxph.cm**-2.s**-1phot.flux.density;em.gamma.harddoublee_FluxV[2.6e-12/9.1e-11] Uncertainty in VHE fluxph.cm**-2.s**-1stat.errordoubleEnergyXEnergy range, Xrayinstr.bandpasscharEnergyVEnergy range, VHEinstr.bandpasscharJ/ApJS/248/29/fig7VHE flux vs. X-ray flux in three X-ray and three VHE energy bands for April 15 -- Data behind Figure 7recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMJDcModified Julian date, bin centerdtime.epochdoubleFluxX[3.8e-12/2.2e-09] Xray Flux, erg/cm2/smW.m**-2phot.flux;em.X-raydoublee_FluxX[1e-12/1.5e-10] Uncertainty in Xray FluxmW.m**-2stat.errordoubleFluxV[6.7e-12/1.3e-09] VHE fluxph.cm**-2.s**-1phot.flux.density;em.gamma.harddoublee_FluxV[2.6e-12/9.1e-11] Uncertainty in VHE fluxph.cm**-2.s**-1stat.errordoubleEnergyXEnergy range, Xrayinstr.bandpasscharEnergyVEnergy range, VHEinstr.bandpasscharJ/ApJS/248/29/fig12Normalized VHE and X-ray light curves with 15-min time bins for 2013 April 11-19 (Data behind Figure B1)Sim[0/1] Simultaneity (2)meta.codeintEnergyEnergy bandinstr.bandpasscharCompComplementary bandinstr.bandpasscharDateUT observation date'Y/M/D'time.epochcharInstInstrument (NuSTAR, MAGIC or VERITAS)meta.id;instrcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTime[-3.2/9.8] Time in hours from midnighthtime.epochfloatdT[0.01/0.14] Time bin halfwidthhtime.intervalfloatFlux[0.3/2.4] Normalized Flux (1)phot.flux;arith.ratiofloate_Flux[0.004/0.8] Uncertainty in normalized fluxstat.error;phot.fluxfloatJ/ApJS/248/29/figcLight curves from 2013 April 11-14, 16 in three X-ray bands and three VHE gamma-ray bands (Data behind Figures C1-C5)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintDateUT observation date'Y/M/D'time.epochcharTime[-3.2/9.8] Time in hours from MJD 56397htime.epochfloatdT[0.018/0.14] Time bin halfwidthhtime.intervalfloatFluxFlux with Instrument in Energy Range having Unitphot.flux.densitydoublee_FluxUncertainty in Fluxstat.error;phot.fluxdoubleInstInstrument (NuSTAR, MAGIC or VERITAS)meta.id;instrcharEnergyEnergy range / Filterinstr.bandpasscharx_FluxFlux units (erg/cm2/s or ph/cm2/s)meta.unit;phot.fluxchar