J/AJ/157/3ivo://CDS.VizieR/J/AJ/157/3doi:10.26093/cds/vizier.51570003CDSLatkovic O.Cseki A.Djurasevic G.Essam A.Hamed A.S.Youssef S.M.2019-05-27T08:43:37Z2019-05-14T07:08:17ZCDS support team

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

cds-question@unistra.frwhite-dwarf-starsdwarf-starseclipsing-binary-starsinfrared-photometryvisible-astronomybroad-band-photometryWe observed the post-common-envelope eclipsing binary with a white dwarf component, QS Vir, using the 1.88 m telescope of Kotammia Observatory in Egypt. The new observations were analyzed together with all multicolor light curves available online (sampling a period of 25 yr), using a full-feature binary system modeling software based on Roche geometry. This is the first time complete photometric modeling was done with most of these data. QS Vir is a detached system, with the red dwarf component underfilling its Roche lobe by a small margin. All light curves feature out-of-eclipse variability that is associated with ellipsoidal variation, mutual irradiation and irregularities in surface brightness of the tidally distorted and magnetically active red dwarf. We tested models with one, two, and three dark spots and found that one spot is sufficient to account for the light curve asymmetry in all data sets, although this does not rule out the presence of multiple spots. We also found that a single spotted model cannot fit light curves observed simultaneously in different filters. Instead, each filter requires a different spot configuration. To thoroughly explore the parameter space of spot locations, we devised a grid-search procedure and used it to find consistent solutions. Based on this, we conclude that the dark spot responsible for light curve distortions has been stable for the past 15 yr, after a major migration that happened between 1993 and 2002, possibly due to a flip-flop event.2019AJ....157....3Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/157/3CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/322 : UCAC4 Catalogue (Zacharias+, 2012)J/PASJ/59/955 : UBVRI differential photometry of BH Vir (Xiang+, 2007)J/A+A/513/L7 : Post common envelope binaries from SDSS. VIIIJ/MNRAS/413/1121 : SDSS post-common envelope binaries. Xhttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/157/3https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/157/3http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/157/3https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/157/3https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/157/3http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/157/3GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/157/3/table2 (Information about the variable, comparison, and check stars (from the UCAC4 catalog, Zacharias et al. 2012, Cat. I/322))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/157/3/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/157/3/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/157/3/table2?GETtext/xml+votable180.050000true207.46645833-13.227083330.0055555555555555566/256661.143914381504295e-19 1.7798557115773645e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/157/3?format=asciiOpticalInfrareddefaultJ/AJ/157/3/table2Information about the variable, comparison, and check stars (from the UCAC4 catalog, Zacharias et al. 2012, Cat. I/322)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintStarStar namemeta.id;meta.maincharUCAC4UCAC4 designation (UCAC4 FFF-NNNNNN)meta.idcharRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainBmag[14.176/15.442] B band magnitudemagphot.mag;em.opt.BfloatVmag[13.415/14.867] V band magnitudemagphot.mag;em.opt.VfloatJmag[10.829/13.716] J band magnitudemagphot.mag;em.IR.JfloatHmag[10.271/13.427] H band magnitudemagphot.mag;em.IR.HfloatLCLight curvesmeta.ref.urlcharSimbadSimbad column added by the CDSmeta.ref.urlcharJ/AJ/157/3/table3New BVRI light curves of QS VirrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric Julian Date of observationdtime.epochdoublePhase[0.00237/0.99992] Orbital phasetime.phasedoublemag[11.99887/16.7399] Magnitude in Bandmagphot.magdoubleBand[BVRI] Passband used (Bessell B, V, R or I)instr.setupcharSeas[S15/S16] Observational season (2015 or 2016)time.epochchar