J/A+AS/132/83ivo://CDS.VizieR/J/A+AS/132/83CDSBai J.MXie G.Z.Li K.H.Zhang X.Liu W.W.1998-10-14T10:00:54Z1998-10-14T09:52:53ZCDS support team

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

cds-question@unistra.frbl-lacertae-objectsinfrared-photometryvisible-astronomyWide-band photometrySeven BL Lac objects have been photometrically observed in an effort to study the difference of optical intraday variability between the radio-selected BL Lac objects (RBLs) and X-ray-selected BL Lac objects (XBLs). The objects we observed are selected arbitrarily. They are four RBLs, PKS 0735+178, PKS 0754+101, OJ 287 and BL Lac, and three XBLs, H 0323+022, H 0548-322 and H 2154-304. During the observation all of them exhibited microvariation, and H 0323+022 and H 0548-322 sometimes showed brightness oscillation. PKS 0735+178 and BL Lac were in their faint states and not very active. It seems that RBLs do not show microvariability more frequently than XBLs.1998A&AS..132...83Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+AS/132/83CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+AS/132/83https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+AS/132/83http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+AS/132/83https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+AS/132/83https://vizier.iucaa.in/viz-bin/votable?-source=J/A+AS/132/83http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+AS/132/83GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticalInfrareddefaultJ/A+AS/132/83/table2Photometric data of seven BL Lac objectsBand[BVRI] Filter usedmeta.code;instr.filterchare_magOne sigma uncertainty on magmagstat.errorfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintDateObservation datetime.epochnullableJDJulian Datedtime.epochdoublemagMagnitudemagphot.mag;em.opt.VfloatObjectName of the object observedmeta.id;meta.mainchar