J/A+A/544/L6ivo://CDS.VizieR/J/A+A/544/L6doi:10.26093/cds/vizier.35449006CDSVornanen T.Berdyugin A.2018-01-11T06:15:25Z2012-08-03T11:28:23ZCDS support team

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

cds-question@unistra.frwhite-dwarf-starsphotometryThe intensity profiles of the C2 Swan bands in cool DQ white dwarfs cannot be adequately fitted with models that otherwise succesfully reproduce spectral features of the molecule CH in these stars. Initial modelling showed that a two-component atmosphere in the style of a spot might be able to solve the problem. We photometrically observed the two cool DQ white dwarfs GJ1117 and EGGR78 to search for variability caused by stellar spots. We have not found any such variability, but we estimate the effects of hypothetical spots on lightcurves. We also estimate detection probabilities for spots in different configurations. Alternative explanations of the problem are needed and briefly discussed.2012A&A...544L...6Vhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/544/L6CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/544/L6https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/544/L6http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/544/L6https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/544/L6https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/544/L6http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/544/L6GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/544/L6/table1 (Observing log)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/544/L6/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/544/L6/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/544/L6/table1?GETtext/xml+votable180.050000true169.5629583-3.23497220.005555555555555556Cone search capability for table J/A+A/544/L6/images (List of all FITS images, in "fits" subdirectory)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/544/L6/images?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/544/L6/images?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/544/L6/images?GETtext/xml+votable180.050000true169.5629583-3.23497220.005555555555555556Associated datahttps://cdsarc.cds.unistra.fr/assocdata/?obs_collection=J/A+A/544/L66/5065 26929https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/544/L6?format=asciiOpticaldefaultJ/A+A/544/L6/table1Observing logNameStar namemeta.id;meta.maincharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintDateObservation datetime.epoch;obsnullableNBNumber of B imagesmeta.numberintNR? Number of R imagesmeta.numberintnullableDirDirectory containing the fits images in subdirectory fitsmeta.id;meta.fileintFilesList FITS files for this datemeta.ref.urlcharSimbadSimbad column added by the CDSmeta.refchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainJ/A+A/544/L6/imagesList of all FITS images, in "fits" subdirectoryrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar name ("EGGR78" or "GJ1117")meta.id;meta.maincharF[BR] Filter (B or R)meta.code;instr.filtercharFileNameName of FITS file, in "fits" subdirectorymeta.id;meta.fitscharObsDateDate and time of observationstime.epoch;obsnullableDownloadDownload the FITS file (1024x1024)meta.ref.urlcharSimbadSimbad column added by the CDSmeta.refchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.main