J/ApJ/685/947ivo://CDS.VizieR/J/ApJ/685/947doi:10.26093/cds/vizier.16850947CDSPoretti E.Clementini G.Held E.V.Greco C.Mateo M.,Dell'Arciprete L.Rizzi L.Gullieuszik M.Maio M.2018-01-30T07:18:08Z2010-12-23T10:02:20ZCDS support team

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

cds-question@unistra.frvariable-starsvisible-astronomybroad-band-photometrygalaxiesWe have carried out an intensive survey of the northern region of the Fornax dwarf spheroidal galaxy with the aim of detecting the galaxy's short-period pulsating stars (P<0.25 days). Observations collected over three consecutive nights with the Wide Field Imager of the 2.2m MPI telescope at ESO allowed us to detect 85 high-amplitude (0.20-1.00mag in B light) variable stars with periods in the range from 0.046 to 0.126 days, similar to SX Phoenicis stars in Galactic metal-poor stellar populations. The plots of the observed periods vs. the B and V magnitudes show a dispersion largely exceeding the observational errors. To disentangle the matter, we separated the first-overtone from the fundamental-mode pulsators and tentatively identified a group of subluminous variables, about 0.35mag fainter than the others. Their nature as either metal-poor intermediate-age stars or stars formed by the merging of close binary systems is discussed. The rich sample of the Fornax variables also led us to reconstruct the period-luminosity relation for short-period pulsating stars. An excellent linear fit, M_V_=-1.83(+/-0.08)-3.65(+/-0.07)logP_F_, was obtained using 153 {delta} Scuti and SX Phoenicis stars in a number of different stellar systems.2008ApJ...685..947Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/685/947CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/AJ/131/912 : BR photometry of Fornax dSph center (Olszewski+, 2006)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/685/947https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/685/947http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/685/947https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/685/947https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/685/947http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/685/947GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/685/947/table2 (Identification and properties of the Fornax dSph SX Phe stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/685/947/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/685/947/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/685/947/table2?GETtext/xml+votable180.050000true40.309167-34.3840830.0055555555555555566/359693.8814057807558857e-19 4.826256797203527e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/685/947?format=asciiOpticaldefaultJ/ApJ/685/947/table2Identification and properties of the Fornax dSph SX Phe starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordint[PCH2008]Variable identification (N-VNNNNN) (1)meta.id;meta.maincharprimaryRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainPerPerioddtime.perioddoubleTmaxTime of maximum: HJD-2452222.0dtime.epochfloat<Bmag>Mean WFI B-band mean magnitudemagphot.mag;em.opt.BfloatBampWFI B-band amplitudemagphot.mag;em.opt.Bfloat<B-V>? WFI mean B-V color indexmagphot.color;em.opt.B;em.opt.VfloatnullableTypeVariability type (2)meta.notecharLCPlot the light curvemeta.ref.urlcharJ/ApJ/685/947/table3BV photometry of the Fornax dSph SX Phe starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordint[PCH2008]Variable identification (N-VNNNNN)meta.id;meta.maincharFilt[BV] Filter usedinstr.setup;instr.filtercharPerPerioddtime.perioddoubleHJDHeliocentric Julian Datedtime.epochdoublemagObserved magnitude in Filtmagphot.magfloat