J/ApJ/848/103ivo://CDS.VizieR/J/ApJ/848/103doi:10.26093/cds/vizier.18480103CDSKapanadze B.Dorner D.Romano P.Vercellone S.Kapanadze S.,Tabagari L.2023-02-13T15:20:51Z2018-07-16T10:24:56ZCDS support team

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

cds-question@unistra.frbl-lacertae-objectsx-ray-sourcesultraviolet-astronomyWe present the results of the Swift observations of the nearby BL Lac object Mrk421 during 2013 November-2015 June. The source exhibited a strong long-term variability in the 0.3-10keV band, with a maximum-to-minimum flux ratio of 13, and underwent X-ray flares by a factor of 1.8-5.2 on timescales of a few weeks or shorter. The source showed 48 instances of intraday flux variability in this period, which sometimes was observed within the 1 ks observational run. It was characterized by fractional amplitudes of 1.5(0.3)%-38.6(0.4)% and flux doubling/halving times of 2.6-20.1hr. The X-ray flux showed a lack of correlation with the TeV flux on some occasions (strong TeV flares were not accompanied by comparable X-ray activity and vice versa), indicating that the high-energy emission in Mrk421 was generated from an emission region more complex than a single zone. The best fits of the 0.3-10keV spectra were mainly obtained using the log-parabola model, showing a strong spectral variability that generally followed a "harder-when-brighter" trend. The position of the synchrotron spectral energy distribution peak showed an extreme range from a few eV to ~10keV that happens rarely in blazars.2017ApJ...848..103Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/848/103CatalogResearchIsServedByTAP VizieR generic servicerelated-toIX/43 : 1SXPS Swift X-ray telescope point source catalogue (Evans+ 2014)VIII/76 : Leiden/Argentine/Bonn (LAB) Survey of Galactic HI (Kalberla+ 2005)J/ApJS/232/7 : 8yr R-band photopolarimetric data of Mrk 421 (Fraija+, 2017)J/ApJ/831/102 : Swift and NuSTAR obs. of the BL Lac Mrk 421 (Kapanadze+, 2016)J/A+A/593/A91 : Mrk 421 multi-wavelength variability, 2007-2009 (Ahnen+, 2016)J/ApJS/222/6 : 4.5yr obs. of Mrk421 with ARGO-YBJ + Fermi (Bartoli+, 2016)J/ApJS/218/23 : Fermi LAT third source catalog (3FGL) (Acero+, 2015)J/A+A/578/A22 : Mrk421 in March 2010 (Aleksic+, 2015)J/A+A/576/A126 : The 2009 multiwavelength campaign on Mrk421 (Aleksic+, 2015)J/MNRAS/439/690 : Optical/{gamma}-ray variability in blazars (Hovatta+, 2014)J/MNRAS/438/3058 : 15GHz variability of {gamma}-ray blazars (Richards+, 2014)J/A+A/563/A57 : Long-term variability of AGN at hard X-rays (Soldi+, 2014)J/ApJS/209/14 : The Swift/BAT hard X-ray transient monitor (Krimm+, 2013)J/A+A/559/A75 : 43GHz observation of the blazar Mrk 421 (Blasi+, 2013)J/A+A/548/A79 : INTEGRAL-OMC opt. variable sources (Alfonso-Garzon+, 2012)J/A+A/545/A117 : Monitoring of Mrk 421 at 15 and 24 GHz (Lico+, 2012)J/ApJS/194/29 : Observations of blazars at 15GHz (Richards+, 2011)J/AJ/137/5022 : Variability of radio-bright BL Lac objects (Nieppola+, 2009)J/ApJ/663/320 : IR-through-UV extinction curve (Fitzpatrick+, 2007)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/848/103https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/848/103http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/848/103https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/848/103https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/848/103http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/848/103GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapX-rayUVdefaultJ/ApJ/848/103/table1The summary of the XRT and UVOT observations in 2013 November - 2015 Junee_XRT[0.08/1.2] Uncertainty in XRTct/sstat.errorfloatMJDModified Julian date of the observation startdtime.epochdoubleXRT[7/100] Observation-binned 0.3-10keV count ratect/sphot.count;em.X-rayfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintobsID[31202141/92204008] Observation identifiermeta.id;obslongprimarystUTC date of observation startstime.start;obsnullableendUTC date of observation endstime.end;obsnullableExp[22/10000] Exposure timestime.duration;obs.exposureintuvw1mag[11/12.1]? De-reddened Swift/UVOT uvw1 band magnitudemagphot.mag;em.UVfloatnullablee_uvw1mag[0.03/0.2]? Uncertainty in uvw1magmagstat.error;phot.magfloatnullableFuvw1[13.2/33.4]? De-reddened Swift/UVOT uvw1 band flux densitymJyphot.flux;em.UVfloatnullablee_Fuvw1[0.05/1.3]? Uncertainty in Fuvw1mJystat.errorfloatnullableuvm2mag[11/12.2]? De-reddened Swift/UVOT uvm2 band magnitudemagphot.mag;em.UVfloatnullablee_uvm2mag[0.03/0.2]? Uncertainty in uvm2magmagstat.error;phot.magfloatnullableFuvm2[10.8/29.1]? De-reddened Swift/UVOT uvm2 band flux densitymJyphot.flux;em.UVfloatnullablee_Fuvm2[0.1/0.5]? Uncertainty in Fuvm2mJystat.errorfloatnullableuvw2mag[11/12]? De-reddened Swift/UVOT uvw2 band magnitudemagphot.mag;em.UVfloatnullablee_uvw2mag[0.03/0.2]? Uncertainty in uvw2magmagstat.error;phot.magfloatnullableFuvw2[11.7/28]? De-reddened Swift/UVOT uvw2 band flux densitymJyphot.flux;em.UVfloatnullablee_Fuvw2[0.1/1.2]? Uncertainty in Fuvw2mJystat.errorfloatnullableRResults for this observation (tables 4 and 7)meta.ref.urlcharJ/ApJ/848/103/table3Summary of the intraday 0.3-10keV variabilities in 2013 November - 2015 JuneORSOrbit segment (2)obs.paramcharEpMin[0.009/7.3]? Min position of the SED peak in LP modelkeVstat.paramfloatnullablebMax[0.1/0.5]? Max curvature parameter in LP modelstat.paramfloatnullablee_bMax[0.03/0.08]? Uncertainty in bMaxstat.errorfloatnullablee_EpMin[0.004/0.5]? Uncertainty in EpMinkeVstat.errorfloatnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSig[99.5/99.9] Intra-day Variability Significance (1)stat.fit.goodness;src.varfloatobsID1[31202142/92204003] First observation identifier (2)meta.id;obslongobsID2[35014107/92204004]? Last observation identifier (2)meta.id;obslongnullableOrbitOrbit of obsID1, Or# (2)obs.paramcharDate1UT Date of observation 1 (2)time.epoch;obsnullableDate2UT Date of observation 2 (2)time.epoch;obsnullableExp[0.1/24] Total length of the particular observation (2)htime.expofloatchi2[1.9/3325.6] Reduced {chi}^2^ parameterstat.paramdoubleDOF[1/24] Fit degrees of freedomstat.fit.dofintFvar[1.4/38.6] Fractional variability amplitude%phot.mag;arith.ratiofloate_Fvar[0.2/1.4] Uncertainty in Fvar%stat.errorfloataMin[1.7/2.6]? Min photon index at the energy E1 in LP model (3)spect.indexfloatnullablee_aMin[0.01/0.3]? Uncertainty in aMinstat.errorfloatnullableaMax[1.8/2.7]? Max photon index at the energy E1 in LP model (3)spect.indexfloatnullablee_aMax[0.01/0.03]? Uncertainty in aMaxstat.errorfloatnullableGamMin[1.8/2.5]? Min photon index in PL model (3)spect.indexfloatnullablee_GamMin[0.01/0.02]? Uncertainty in GammaMinstat.errorfloatnullableGamMax[2/2.4]? Max photon index in PL model (3)spect.indexfloatnullablee_GamMax[0.02]? Uncertainty in GammaMaxstat.errorfloatnullablebMin[0.08/0.4]? Min curvature parameter in LP modelstat.paramfloatnullablee_bMin[0.02/0.07]? Uncertainty in bMinstat.errorfloatnullableEpMax[0.09/9.2]? Max position of the SED peak in LP modelkeVstat.paramfloatnullablee_EpMax[0.03/0.7]? Uncertainty in EpMaxkeVstat.errorfloatnullableHRMin[0.2/1.1]? Minimum hardness ratiophot.flux;stat.mindoublenullablee_HRMin[0.01/0.04]? Uncertainty in HRMinstat.errordoublenullableHRMax[0.2/1.2]? Maximum hardness ratiophot.flux;stat.maxfloatnullablee_HRMax[0.009/0.2]? Uncertainty in HRMaxstat.errorfloatnullableJ/ApJ/848/103/table4The results of the XRT spectral analysis with the logparabolic modelDOF[12/276] Fit degrees of freedomstat.fit.dofintobsID[31202141/94204006] Observation identifiermeta.id;obslongrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordinta[1.7/2.7] Model parameter, photon index at the energy E1meta.code;stat.param;meta.modelledfloate_a[0.01/0.03] Uncertainty in astat.errorfloatb[0.08/0.5] Model parameter, curvature parameterstat.param;meta.modelledfloate_b[0.03/0.08] Uncertainty in bstat.errorfloatEp[0.005/9.2] Model parameter, position of the SED peakkeVstat.param;meta.modelled;stat.maxfloate_Ep[0.003/0.7] Uncertainty in EpkeVstat.errorfloatK[0.06/1.8] Model parameter, normalization factorstat.paramfloate_K[0.001/0.04] Uncertainty in Kstat.errorfloatchi2[0.8/1.2] Reduced {chi}^2 parameterstat.paramfloatlogFS[-9.7/-8.7] Log unabsorbed 0.3-2 keV Fluxlog(mW.m**-2)phot.flux;em.X-rayfloate_logFS[0.004/0.009] Uncertainty in logFSlog(mW.m**-2)stat.errorfloatlogFH[-10.3/-0.1] Log unabsorbed 2-10 keV Fluxlog(mW.m**-2)phot.flux;em.X-rayfloate_logFH[0.002/0.03] Uncertainty in logFHlog(mW.m**-2)stat.errorfloatlogFT[-9.9/-8.5] Log unabsorbed 0.3-10 keV Fluxlog(mW.m**-2)phot.flux;em.X-rayfloate_logFT[0.004/0.07] Uncertainty in logFHlog(mW.m**-2)stat.errorfloatHR[0.2/1.2] Hardness ratio (G2)phot.flux;arith.ratiofloate_HR[0.008/0.2] Uncertainty in HRstat.errorfloatORSOrbit/Segment code for model fit (G1)obs.paramcharJ/ApJ/848/103/table7The results of the XRT spectral analysis with a simple PL modelobsID[35014092/35014210] Observation identifiermeta.id;obslongrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintORSOrbit/Segment code for model fit (G1)obs.paramcharGamma[1.8/2.8] Photon index in PL modelmeta.code;spect.index;meta.modelledfloate_Gamma[0.01/0.02] Uncertainty in Gammastat.errorfloatK[0.04/0.5] Normalizationstat.paramfloate_K[0.001/0.02] Uncertainty in Kstat.errorfloatchi2[0.8/1.2] Reduced {chi}^2^ parameterstat.paramfloatDOF[106/276] Fit degrees of freedomstat.fit.dofintlogFS[-9.8/-8.9] Log unabsorbed 0.3-2 keV Fluxlog(mW.m**-2)phot.flux;em.X-rayfloate_logFS[0.004/0.008] Uncertainty in logFSlog(mW.m**-2)stat.errorfloatlogFH[-10.4/-8.9] Log unabsorbed 2-10 keV Fluxlog(mW.m**-2)phot.flux;em.X-rayfloate_logFH[0.009/0.02] Uncertainty in logFHlog(mW.m**-2)stat.errorfloatlogFT[-9.7/-8.6] Log unabsorbed 0.3-10 keV Fluxlog(mW.m**-2)phot.flux;em.X-rayfloate_logFT[0.005/0.007] Uncertainty in logFHlog(mW.m**-2)stat.errorfloatHR[0.2/1.1] Hardness ratio (G2)phot.flux;arith.ratiofloate_HR[0.009/0.04] Uncertainty in HRstat.errorfloat