J/A+A/636/A77ivo://CDS.VizieR/J/A+A/636/A77doi:10.26093/cds/vizier.36360077CDSSkopal A.Shugarov S.Yu.Munari U.Masetti N.Marchesini E.,Komzik R.M.Kundra E.Shagatova N.Tarasova T.N.Buil C.Boussin C.,Shenavrin V.I.Hambsch F.-J.Dallaporta S.Frigo A.Garde O.,Zubareva A.Dubovsky P.A.Kroll P.2023-04-24T12:11:00Z2020-04-21T07:12:21ZCDS support team

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

cds-question@unistra.frcataclysmic-variable-starsinfrared-photometryvisible-astronomybroad-band-photometryphotographic-photometryThe star V426 Sge (HBHA 1704-05), originally classified as an emission-line object and a semi-regular variable, brightened at the beginning of August 2018, showing signatures of a symbiotic star outburst. We aim to confirm the nature of V426 Sge as a classical symbiotic star, determine the photometric ephemeris of the light minima, and suggest the path from its 1968 symbiotic nova outburst to the following 2018 Z And-type outburst. We re-constructed an historical light curve (LC) of V426 Sge from approximately the year 1900, and used original low- (R~500-1500; 330-880nm) and high-resolution (R~11000-34000; 360-760nm) spectroscopy complemented with Swift-XRT and UVOT, optical UBVR_C_I_C_ and near-infrared $JHKL$ photometry obtained during the 2018 outburst and the following quiescence. The historical LC reveals no symbiotic-like activity from ~1900 to 1967. In 1968, V426 Sge experienced a symbiotic nova outburst that ceased around 1990. From approximately 1972, a wave-like orbitally related variation with a period of 493.4+/-0.7-days developed in the LC. This was interrupted by a Z And-type outburst from the beginning of August 2018 to the middle of February 2019. At the maximum of the 2018 outburst, the burning white dwarf (WD) increased its temperature to >~2x10^5^K, generated a luminosity of ~7x10^37^(d/3.3kpc}^2^erg/s, and blew a wind at the rate of ~3x10^-6^M_{sun}_/yr. Our spectral energy distribution models from the current quiescent phase reveal that the donor is a normal M4-5 III giant characterised with Teff~3400K, R_G_~106(d/3.3kpc})R_{sun}_ and L_G_~1350(d/3.3kpc})^2^L_{sun}_ and the accretor is a low-mass ~0.5M_{sun}_ WD. During the transition from the symbiotic nova outburst to the quiescent phase, a pronounced sinusoidal variation along the orbit develops in the LC of most symbiotic novae. The following eventual outburst is of Z And-type, when the accretion by the WD temporarily exceeds the upper limit of the stable burning. At this point the system becomes a classical symbiotic star.2020A&A...636A..77Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/636/A77CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/636/A77https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/636/A77http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/636/A77https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/636/A77https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/636/A77http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/636/A77GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tap2.367228618189496e-19 6.118840631666147e-19OpticalInfrareddefaultJ/A+A/636/A77/tablea1Observed U,B,V,Rc,Ic magnitudesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJDJulian date (UT), JD-2400000time.epochdoubleObs.dateObservation date, YYYY/MM/DD.dddstime.epoch;obsnullableUmag? U magnitudemagphot.mag;em.opt.Ufloatnullablee_Umag? Error in U magnitudemagstat.error;phot.magfloatnullableBmag? B magnitudemagphot.mag;em.opt.Bfloatnullablee_Bmag? Error in B magnitudemagstat.error;phot.magfloatnullableVmag? V magnitudemagphot.mag;em.opt.Vfloatnullablee_Vmag? Error in V magnitudemagstat.error;phot.magfloatnullableRcmag? Rc magnitudemagphot.mag;em.opt.Rfloatnullablee_Rcmag? Error in Rc magnitudemagstat.error;phot.magfloatnullableIcmag? Ic magnitudemagphot.mag;em.opt.Ifloatnullablee_Icmag? Error in Ic magnitudemagstat.error;phot.magfloatnullableObsObservatory (1)meta.id;instr.obstycharJ/A+A/636/A77/tablea2Observed B,V,Rc,Ic magnitudesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJDJulian date (UT), JD-2400000time.epochdoubleObs.dateObservation date, YYYY/MM/DD.dddstime.epoch;obsnullableBmag? B magnitudemagphot.mag;em.opt.Bfloatnullablee_Bmag? Error in B magnitudemagstat.error;phot.magfloatnullableVmag? V magnitudemagphot.mag;em.opt.Vfloatnullablee_Vmag? Error in V magnitudemagstat.error;phot.magfloatnullableRcmag? Rc magnitudemagphot.mag;em.opt.Rfloatnullablee_Rcmag? Error in Rc magnitudemagstat.error;phot.magfloatnullableIcmag? Ic magnitudemagphot.mag;em.opt.Ifloatnullablee_Icmag? Error in Ic magnitudemagstat.error;phot.magfloatnullableTelTelescope of the ANS collaborationinstr.telintJ/A+A/636/A77/tablea3Photographic m_pg and m_pv magnitudesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJDJulian date (UT), JD-2400000time.epochdoubleObs.dateObservation date, YYYY/MM/DD.dddtime.epoch;obsnullablepgmag? Photographic m_pg_ magnitudemagphot.mag;em.optfloatnullablee_pgmag? Error in m_pg_ magnitudemagstat.error;phot.magfloatnullablepvmag? Photographic m_pv_ magnitudemagphot.mag;em.optfloatnullablee_pvmag? Error in m_pv_ magnitudemagstat.error;phot.magfloatnullableArchPlate archive (1)obs.fieldchar