J/AJ/109/817ivo://CDS.VizieR/J/AJ/109/817doi:10.26093/cds/vizier.51090817CDSAntokhin I.Bertrand J.-F.Lamontagne R.Moffat A.F.J.Matthews J.2023-04-06T16:50:12Z1997-12-09T20:26:52ZCDS support team

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

cds-question@unistra.frwolf-rayet-starsphotometryWe present the first results of an extensive photometric study of the most intrinsically variable Wolf-Rayet stars: the WN8 subclass. Some 375 individual differential observations of WR16 and WR40 were obtained over a contiguous interval of ~3 months in a narrow visual continuum bandpass. Over the same interval, we obtained roughly 200 broadband V observations of the fainter WN8 stars WR66 and WR82. All four WN8 stars show significant random variability on time scales of hours to ~a day -- probably related to the stochastic formation, propagation, and decay of emitting/scattering inhomogeneities in the winds. Unlike for WR66 and WR82, the photometric behaviour of WR16 and WR40 is more deterministic with ~two possible periods in the range ~2-30 days -- possibly related to some kind of LBV, binary, or rotation phenomenon. In addition, WR82 shows a possible secular decline during the 3 months and WR66 reveals a clear periodicity of 3.51 h. This short period may be related to nonradial pulsations or a spiral-in binary process invoking a low-mass, compact companion as seen in the massive x-ray binary Cyg X-3, a WN7 + c system of period 4.8 h.1995AJ....109..817Ahttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/109/817CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/109/817https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/109/817http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/109/817https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/109/817https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/109/817http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/109/817GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/AJ/109/817/table1Comparison stars for the WN8 starsb-v[]? b-v colormagphot.color;em.opt.B;em.opt.VfloatCmpComparison star number (C1 or C2)meta.idcharNameComparison star namemeta.idcharSpSpectral typesrc.spTypecharVmagV magnitudemagphot.mag;em.opt.VfloatWR-CDifference between comparison and WRmagphot.mag;arith.difffloate_WR-CError (sigma) in WR-Cmagstat.errorfloatC2-C1? Difference between comparison starmagphot.mag;arith.difffloate_C2-C1? Error (sigma) in C2-C1magstat.errorfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWRWR numbermeta.idcharOtherOther namemeta.idcharvmag[]? v magnitudemagphot.mag;em.opt.VfloatJ/AJ/109/817/table2Narrowband visual photometry for WR16recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric Julian Datedtime.epochdoubleWR-C1WR-C1 differential magnitudemagphot.mag;arith.difffloatWR-C2WR-C2 differential magnitudemagphot.mag;arith.difffloatC2-C1C2-C1 differential magnitudemagphot.mag;arith.difffloatJ/AJ/109/817/table3Narrowband visual photometry for WR40recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric Julian Datedtime.epochdoubleWR-C1WR-C1 differential magnitudemagphot.mag;arith.difffloatWR-C2WR-C2 differential magnitudemagphot.mag;arith.difffloatC2-C1C2-C1 differential magnitudemagphot.mag;arith.difffloatJ/AJ/109/817/table4Broadband visual photometry for WR66recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric Julian Datedtime.epochdoubleWR-C1WR-C1 differential magnitudemagphot.mag;arith.difffloatWR-C2WR-C2 differential magnitudemagphot.mag;arith.difffloatC2-C1C2-C1 differential magnitudemagphot.mag;arith.difffloatJ/AJ/109/817/table5Broadband visual photometry for WR82recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric Julian Datedtime.epochdoubleWR-C1WR-C1 differential magnitudemagphot.mag;arith.difffloatWR-C2WR-C2 differential magnitudemagphot.mag;arith.difffloatC2-C1C2-C1 differential magnitudemagphot.mag;arith.difffloat