J/MNRAS/465/L114ivo://CDS.VizieR/J/MNRAS/465/L114doi:10.26093/cds/vizier.74659114CDSWyrzykowski L.Zielinski M.Kostrzewa-Rutkowska Z.Hamanowicz A.,Jonker P.G.Arcavi I.Guillochon J.Brown P.J.Kozlowski S.,Udalski A.Szymanski M.K.Soszynski I.Poleski R.Pietrukowicz P.,Skowron J.Mroz P.Ulaczyk K.Pawlak M.Rybicki K.A.Greiner J.,Kruhler T.Bolmer J.Smartt S.J.Maguire K.Smith K.2024-08-17T20:17:30Z2018-08-02T08:47:55ZCDS support team

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

cds-question@unistra.fractive-galactic-nucleiultraviolet-photometryinfrared-photometryvisible-astronomyphotometryWe present the discovery and first three months of follow-up observations of a currently on-going unusual transient detected by the Optical Gravitational Lensing Experiment (OGLE-IV) survey, located in the centre of a galaxy at redshift z=0.1655. The long rise to absolute magnitude of -20.5mag, slow decline, very broad He and H spectral features make OGLE16aaa similar to other optical/UV tidal disruption events (TDEs). Weak narrow emission lines in the spectrum and archival photometric observations suggest the host galaxy is a weak-line active galactic nucleus, which has been accreting at higher rate in the past. OGLE16aaa, along with SDSS J0748, seems to form a sub-class of TDEs by weakly or recently active supermassive black holes (SMBHs). This class might bridge the TDEs by quiescent SMBHs and flares observed as "changing-look quasars", if we interpret the latter as TDEs. If this picture is true, the previously applied requirement for identifying a flare as a TDE that it had to come from an inactive nucleus, could be leading to observational bias in TDE selection, thus affecting TDE-rate estimations.2017MNRAS.465L.114Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/465/L114CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/AcA/64/197 : OGLE-IV 2012-2014 transients (Wyrzykowski+, 2014)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/465/L114https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/465/L114http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/465/L114https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/465/L114https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/465/L114http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/465/L114GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapUVOpticalInfrareddefaultJ/MNRAS/465/L114/oglevOGLE16aaa OGLE V light curverecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJDJulian datedtime.epochdoubleVmagOGLE V magnitudemagphot.mag;em.opt.Vfloate_Vmagrms uncertainty on Vmagmagstat.error;phot.magfloatJ/MNRAS/465/L114/ogleiOGLE16aaa OGLE I light curverecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJDJulian datedtime.epochdoubleImagOGLE I magnitudemagphot.mag;em.opt.Ifloate_Imag? rms uncertainty on Imagmagstat.error;phot.magfloatnullableJ/MNRAS/465/L114/swiftOGLE16aaa magnitudes from Swift UVOTlmag3{sigma} limiting magnitudemagphot.magfloatSatSaturation limit (0.98SatLim)maginstr.saturationfloatRateCount ratect/sphot.count;em.UVfloate_Raterms uncertainty on Ratect/sstat.errorfloatAp[3] Aperture radiusarcsecphys.angSizefloatFrametimeFrame time (1)stime.epochfloatExpTimeExposure timestime.duration;obs.exposurefloatTelapseElapsed time of observation (TSTOP - TSTART)stime.epochdoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFilter[UVM2 UVW1 UVW2] Filtermeta.id;instr.filtercharMJDModified Julian datedtime.epochdoublemagMagnitude in filtermagphot.magfloate_magrms uncertainty on magmagstat.error;phot.magfloat