J/A+AS/119/37ivo://CDS.VizieR/J/A+AS/119/37CDSDuijsens M.F.J.van der Hucht K.A.van Genderen A.M.Schwarz H.E.,Linders H.P.J.Kolkman O.M.1997-12-09T18:17:31Z1997-12-09T19:17:27ZCDS support team

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

cds-question@unistra.frwolf-rayet-starsvilnius-photometryvisible-astronomyWide-band photometryWe present and analyse photometric and spectroscopic observations of the WN5 star EZ Canis Majoris obtained over a period of 7 years. We discuss the changing light curve, the shift in phase of the maxima and point to flare type variability seen in one night. Small amplitude variations are reported in another night. We have investigated the change of the average visual magnitude over a time span of 18 years and found a tentative cyclic variation with a time scale of 2425d (6.6yr) with a range of ~0.07mag. This, of course, should be verified. If true, a precession phenomenon may offer an explanation. The trend of the maximum light amplitude of the 3.766d cycle is also investigated and it shows a saw-tooth character with a timescale of ~400d. A possible relation with the magnetic activity of the star is discussed. We conclude that the line emission variability can be caused by both a single star model with an ever-changing wind and a binary (WN+NS) model.1996A&AS..119...37Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+AS/119/37CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/347/583 : EZ CMa spectroscopy (Georgiev+, 1999)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+AS/119/37https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+AS/119/37http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+AS/119/37https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+AS/119/37https://vizier.iucaa.in/viz-bin/votable?-source=J/A+AS/119/37http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+AS/119/37GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/A+AS/119/37/table21*Relative VBLUW data of EZ CMa, epoch IIrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric julian datedtime.epochdoubleDVmagRelative V magnitude (log intensity)magphot.mag;arith.difffloatDBmagRelative B magnitude (log intensity)magphot.mag;arith.difffloatDLmagRelative L magnitude (log intensity)magphot.mag;arith.difffloatDUmagRelative U magnitude (log intensity)magphot.mag;arith.difffloatDWmagRelative W magnitude (log intensity)magphot.mag;arith.difffloatJ/A+AS/119/37/table7Relative Johnson magnitudes and colours of January 11 1987 through January 16 1987recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric julian datedtime.epochdoubleDVmagRelative V Johnson magnitudemagphot.mag;arith.difffloatDB-VRelative Johnson B-V colormagphot.color;arith.difffloatDU-BRelative Johnson U-B colormagphot.color;em.opt.U;em.opt.BfloatJ/A+AS/119/37/table13*Relative VBLUW data of EZ CMa, epoch IrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric julian datedtime.epochdoubleDVmagRelative V magnitude (log intensity)magphot.mag;arith.difffloatDBmagRelative B magnitude (log intensity)magphot.mag;arith.difffloatDLmagRelative L magnitude (log intensity)magphot.mag;arith.difffloatDUmagRelative U magnitude (log intensity)magphot.mag;arith.difffloatDWmagRelative W magnitude (log intensity)magphot.mag;arith.difffloat