J/MNRAS/434/38ivo://CDS.VizieR/J/MNRAS/434/38doi:10.26093/cds/vizier.74340038CDSKopatskaya E.N.Kolotilov E.A.Arkharov A.A.2024-08-06T20:16:41Z2015-02-26T14:37:22ZCDS support team

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

cds-question@unistra.frvariable-starsinfrared-photometryvisible-astronomybroad-band-photometryThe FU Orionis type of variable star (FUor), V1057 Cygni, underwent a nova-like outburst in 1969-1970. Among the FUors, V1057 Cyg is notable for having the most dramatic post-maximum decrease in brightness. Thus, photometric monitoring of this object is important for interpretations of the cause of this event. Here, we study the behaviour of V1057 Cyg over the last 25 years on the basis of our optical and infrared observations. The optical and near-infrared observations of V1057 Cyg started in 1974, and we present all our data (up to the end of 2011), including 1085 and 167 nights of optical and infrared photometry, respectively. The UBVRIJHKLM light curves for 1985-2011 show that despite the increased photometric activity, after a rapid decrease in brightness in the mid-1990s, the average level of brightness remained practically constant. After the object becomes fainter than V~11.5mag, a swerve appears in the track of the colour-magnitude diagram. The light variability shows a different periodicity in different spectral regions. We have discovered a period of 1631+/-60d in the BVR bands (1995-2011) and 523+/-40d in the RIJHK bands (2002-2011) with amplitudes of 0.5-0.3mag. The 523-d period is presumably correlated with the changes in the radial velocity of an emission component in LiI. We conclude that the observed properties of the FUor star V1057 Cyg are in accordance with current models of FUors involving binary or multiple systems.2013MNRAS.434...38Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/434/38CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/AZh/88/34 : Long-term (1984-2008) JHKLM photometry of stars (Shenavrin+ 2011)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/434/38https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/434/38http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/434/38https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/434/38https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/434/38http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/434/38GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tap3.533079825982027e-20 6.118840631666147e-19OpticalInfrareddefaultJ/MNRAS/434/38/table1Optical photometry of V1057 Cyg in 1974-2011recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJDJulian date (JD-2400000)dtime.epochdoubleUmag? Johnson U magnitudemagphot.mag;em.opt.Ufloatnullableu_UmagUncertainty flag on Umagmeta.code.errorcharBmag? Johnson B magnitudemagphot.mag;em.opt.Bfloatnullableu_BmagUncertainty flag on Bmagmeta.code.errorcharVmag? Johnson V magnitudemagphot.mag;em.opt.Vfloatnullableu_VmagUncertainty flag on Vmagmeta.code.errorcharRcmag? Cousins R magnitudemagphot.mag;em.opt.RfloatnullableIcmag? Cousins I magnitudemagphot.mag;em.opt.IfloatnullableRjmag? Johnson R magnitudemagphot.mag;em.opt.RfloatnullableIjmag? Johnson I magnitudemagphot.mag;em.opt.IfloatnullableObsObserver name (1)meta.id;obs.observercharJ/MNRAS/434/38/table2JHKLM photometry of V1057 Cyg in 1984-2011recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJDJulian date (JD-2400000)dtime.epochdoubleJmag? Johnson J magnitudemagphot.mag;em.IR.JfloatnullableHmag? Johnson H magnitudemagphot.mag;em.IR.HfloatnullableKmag? Johnson K magnitudemagphot.mag;em.IR.KfloatnullableLmag? Johnson L magnitudemagphot.mag;em.IR.3-4umfloatnullableMmag? Johnson M magnitudemagphot.mag;em.IR.4-8umfloatnullableObsObserver name (1)meta.id;obs.observercharJ/MNRAS/434/38/table3Collective V-band light curve from pre-outburst up to 1990 yearrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJDJulian date (JD-2400000)dtime.epochdoubleVmagV magnitudemagphot.mag;em.opt.Vfloat