J/MNRAS/499/6053ivo://CDS.VizieR/J/MNRAS/499/6053doi:10.26093/cds/vizier.74996053CDSLaurenti M.Vagnetti F.Middei R.Paolillo M.2024-08-21T20:16:37Z2020-11-16T07:33:45ZCDS support team

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

cds-question@unistra.frsurveysactive-galactic-nucleiquasarsAt present, most of the variability studies of active galactic nuclei (AGNs) are based on ensemble analyses. Nevertheless, it is interesting to provide estimates of the individual variability properties of each AGN, in order to relate them with intrinsic physical quantities. A useful dataset is provided by the Catalina Surveys Data Release 2 (CSDR2), which encompasses almost a decade of photometric measurements of ~500 million objects repeatedly observed hundreds of times.We aim to investigate the individual optical variability properties of 795 AGNs originally included in the Multi-Epoch XMMSerendipitous AGN Sample 2 (MEXSAS2). Our goals consist in: (i) searching for correlations between variability and AGN physical quantities; (ii) extending our knowledge of the variability features of MEXSAS2 from the X-ray to the optical.We use the structure function (SF) to analyse AGN flux variations. We model the SF as a power-law, SF(tau)=A(tau/tau_0)^gamma^, and we compute its variability parameters. We introduce the V-correction as a simple tool to correctly quantify the amount of variability in the rest frame of each source.We find a significant decrease of variability amplitude with increasing bolometric, optical and X-ray luminosity. We obtain the indication of an intrinsically weak positive correlation between variability amplitude and redshift, z. Variability amplitude also appears to be positively correlated with alpha_{ox}.The slope of the power-law SF, gamma, is weakly correlated with the bolometric luminosity L_{bol} and/or with the black hole mass M_{BH}. When comparing optical to X-ray variability properties, we find that X-ray variability amplitude is approximately the same for those AGNs with larger or smaller variability amplitude in the optical.On the contrary, AGNs with steeper SF in the optical do present steeper SF in the X-ray, and vice versa.2020MNRAS.499.6053Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/499/6053CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJS/194/45 : QSO properties from SDSS-DR7 (Shen+, 2011)J/A+A/593/A55 : MEXSAS catalogue (Vagnetti+, 2016)J/ApJS/228/9 : Physical parameters of ~300000 SDSS-DR12 QSOs (Kozlowski, 2017)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/499/6053https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/499/6053http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/499/6053https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/499/6053https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/499/6053http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/499/6053GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/499/6053/sample (The reference sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/499/6053/sample?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/499/6053/sample?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/499/6053/sample?GETtext/xml+votable180.050000true1.4901719.963680.0055555555555555565/4419 4421-4425 6814 6826 6/2230 4096-4098 4100 4181 4488 4653 4964-4965 4992 5069 5130 5244 5305 5367 5370 5414 5420 5423 5434 5536 5560 5569-5570 5576 5816 5860 5862 6251 6495 6502 6539 6556-6557 6560 6977 7178 7211 7266 7281 7303 7308 7311 7426 8220 8224 8271 8299 8324 8339 8707 8805 8909 8920 8923 8927 8941 8952 9036 9077 9168 9192 9231 9333 9343 9346 9354 9401 9436 9443-9445 9465 9467-9469 9512 9639 9752 9754 9831 9837 9997 9999 10020 10182-10183 10189-10190 10212 10255 10265-10266 10293 10312 10348 10378-10379 10400-10401 10413-10414 10484 10549 10598 10604 10645 10653 10763 10771 10841 10888 10911-10912 10925 10979 10989 17497 17503 17518 17622 17671 17674-17675 17681-17683 17705 17708 17712-17714 17716 17727 17730 17754 17767 17772 17827-17830 17833 17999 18003 18006 18008-18010 18021-18023 18069 18114 18127 18207 18773 18788-18790 18894 19027 19033 19035-19036 19402 19609 19883 19904 19950 19978 19996 20071 23191 23209 25972 25982 26022 26090 26300 26561 26563 27005 27124 27126 27223 27225 27246-27247 27262 27310 27348 27460 27462 27714-27715 27719 27730 27742 27765 27772-27773 27859-27860 27862 27907 27913 27936 27941 27944 27950 28015 28019 28026 28029 28045 28127 28221 28223 28226 28234 28251 28275 28278 28284 28344 28351 28356 28390 28396 28430 28452 28494 28497 28516-28517 28522 28529 28534-28535 28540-28541 28555 28583 28589 28632 28634 28636-28637 31662 31712 32483 32486 32500 36774 36785-36786 36798 409583.322582951404819e-19 3.852589004194616e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/499/6053?format=asciidefaultJ/MNRAS/499/6053/sampleThe reference sampleSDSSSDSS source name (HHMMSS.ss+DDMMSS.s)meta.idcharRAJ2000Right ascension of SDSS identification (J2000)degpos.eq.ra;meta.mainzRedshiftsrc.redshiftfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMEXSAS2Source number in the MEXSAS2 cataloguemeta.id;meta.mainintDEJ2000Declination of SDSS identification (J2000)degpos.eq.dec;meta.mainlogAUncorrected SF variability amplitudesrc.var.amplitudefloatlogAVcorrV-corrected SF variability amplitudesrc.var.amplitudefloate_logAError on logA_Vcorrstat.errorfloatgammaSlope of the power-law SFspect.index;em.line.Hgammadoublee_gammaError on gammastat.errordoubleRsquaredCoefficient of determinationstat.fit.paramdoublelog(Mbh)Logarithm of black hole masslog(solMass)phys.massfloatlog(Lbol)Logarithm of bolometric luminositylog(1e-07W.Hz**-1)phys.luminosityfloatlog(Edd)Logarithm of Eddington ratiophys.luminosity;arith.ratiofloatVmagAverage magnitude in Johnson's V bandmagphot.mag;em.opt.Vfloatlog(LV)Logarithm of V-band luminositylog(1e-07W.Hz**-1)phys.luminosityfloatlog(LX)Log X-ray luminosity, 0.5-4.5 keV bandlog(1e-07W.Hz**-1)phys.luminosity;em.X-rayfloatNepoNumber of optical observationsmeta.numberintNepxNumber of X-ray observationsmeta.numberintSimbadSimbad column added by the CDSmeta.ref.urlchar