J/ApJ/902/104ivo://CDS.VizieR/J/ApJ/902/104doi:10.26093/cds/vizier.19020104CDSLee J.W.Lee S.-S.Algaba J.-C.Hodgson J.Kim J.-Y.Park J.Kino M.,Kim D.-W.Kang S.Yoo S.Kim S.H.Gurwell M.2022-09-08T13:40:11Z2022-05-10T12:35:14ZCDS support team

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

cds-question@unistra.frinterferometrybl-lacertae-objectsradio-astronomyWe present the results of simultaneous multifrequency imaging observations at 22, 43, 86, and 129GHz of OJ 287. We used the Korean Very Long Baseline Interferometry Network as part of the Interferometric Monitoring of Gamma-ray Bright active galactic nuclei (iMOGABA). The iMOGABA observations were performed during 31 epochs from 2013 January 16 to 2016 December 28. We also used 15GHz OVRO and 225GHz SMA flux density data. We analyzed four flux enhancements in the light curves. The estimated timescales of three flux enhancements were similar with timescales of ~50d at two frequencies. A fourth flux enhancement had a variability timescale approximately twice as long. We found that 225GHz enhancements led the 15GHz enhancements by a range of 7-30d in the time delay analysis. We found the fractional variability did not change with frequency between 43 and 86GHz. We could reliably measure the turnover frequency, {nu}_c_, of the core of the source in three epochs. This was measured to be in a range from 27 to 50GHz and a flux density at the turnover frequency, S_m_, ranging from 3 to 6Jy. The derived SSA magnetic fields, B_SSA_, are in a range from 0.157+/-0.104 to 0.255+/-0.146mG. We estimated the equipartition magnetic field strengths to be in a range from 0.95+/-0.15 to 1.93+/-0.30mG. The equipartition magnetic field strengths are up to a factor of 10 higher than the values of B_SSA_. We conclude that the downstream jet may be more particle energy dominated.2020ApJ...902..104Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/902/104CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+AS/129/569 : BVRI photometry of OJ 287 (Jia Guibin+ 1998)J/A+AS/132/83 : BVRI photometry of 7 BL Lac objects (Bai+ 1998)J/A+AS/136/455 : BVRI photometry of 3 BL Lac objects (Bai+, 1999)J/ApJ/522/846 : Optical monitoring of GeV loud blazars (Xie+, 1999)J/A+AS/146/141 : Intensive monitoring of OJ 287 (Pursimo+, 2000)J/AJ/130/1418 : AGN jet kinematics (Jorstad+, 2005)J/AJ/132/1256 : eim BATC photometry of OJ 287 (Wu+, 2006)J/A+A/450/39 : BVRI photometry of 8 red blazars (Gu+, 2006)J/AJ/134/799 : Multiwaveband polarimetry of 15 AGN (Jorstad+, 2007)J/MNRAS/385/823 : UBVRI light curves of OJ 287 (Zheng+, 2008)J/MNRAS/402/2087 : Opt. polarization of OJ 287 in 2005-2009 (Villforth+, 2010)J/AJ/141/65 : BATC ceimo light curves of OJ 287 (Dai+, 2011)J/ApJ/747/63 : 7mm VLBA observations of BL Lac object OJ287 (Agudo+, 2012)J/A+A/545/A113 : MOJAVE IX. Core shift effects (Pushkarev+, 2012)J/MNRAS/421/1861 : OJ287 polarization and VLBI jet direction (Valtonen+, 2012)J/ApJ/764/5 : BR phot. of 2012 precursor flare in OJ287 (Pihajoki+, 2013)J/A+A/559/A20 : Historical outbursts of OJ287 (Hudec+, 2013)J/A+A/597/A80 : GMVA 86GHz images of OJ 287 (Hodgson+, 2017)J/ApJ/835/275 : OJ 287 flux & pol. during 2016 outburst (Rakshit+, 2017)J/ApJ/846/98 : Jet kinematics of blazars at 43GHz with VLBA (Jorstad+, 2017)J/A+A/601/A12 : S5 0716+714 VLBI K- and Q-band variability (Lee+, 2017)J/ApJ/862/1 : Rotation reversals in OJ 287 polarization (Cohen+, 2018)J/A+A/609/A68 : Full-Stokes polarimetry of 5 radio sources (Myserlis+, 2018)J/A+A/610/A74 : OJ 287 far-infrared photometry (Kidger+, 2018)J/A+A/619/A88 : OJ287 high cadence polarization monitoring (Myserlis+, 2018)J/A+A/626/A60 : F-GAMMA 2.6-43GHz radio data over 2007-2015 (Angelakis+, 2019)J/AJ/157/95 : Optical variability of OJ 287 in 2016-2017 (Gupta+, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/902/104https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/902/104http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/902/104https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/902/104https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/902/104http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/902/104GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapRadiodefaultJ/ApJ/902/104/imagesCombined table from original tablesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObs[2013/2016] Year of the observation epochtime.epochMJD[56308/57751] Modified Julian Date of observationdtime.epochintBandObserving frequency band (G1)em.freqcharBmaj[0.86/9.8] Major axis of restoring beammasphys.angSize;instr.beamfloatBmin[0.4/3.72] Minor axis of restoring beammasphys.angSize;instr.beamfloatBPA[-89.2/89.2] Position angle of restoring beam major axisdegpos.posAng;instr.beamfloatSKVN[1.36/8.5] Total cleaned KVN flux densityJyphot.flux.density;em.radiofloatSp[1.3/8.4] Peak flux densityJy/beamphot.flux.density;stat.maxfloatsigma[8/363] Off-source RMS in imageJy/beamstat.stdev;obs.imageintD[7/470] Dynamic range of imagestat.snrintxi-r[0.4/0.9] Quality of residual noise in image (1)instr.det.noisefloatStot[1.3/8.4] Model flux density (2)Jyphot.flux.densityfloate_Stot[0.02/2.3] Uncertainty in StotJystat.errorfloatSpeak[1/8.4] Peak brightness (2)Jy/beamphot.flux.densityfloate_Speak[0.01/1.4] Uncertainty in SpeakJy/beamstat.errorfloatl_dLimit flag on dmeta.code.errorchard[0.06/1.3] Size of the core component (2)masphys.angSizefloate_d[0/0.6]? Uncertainty in dmasstat.errorfloatnullablel_TbLimit flag on Tbmeta.code.errorcharTb[0.49/267.6] Measured brightness temperature1e+09Kphys.temperaturefloate_Tb[0.01/3.4]? Uncertainty in Tb1e+09Kstat.errorfloatnullable