J/MNRAS/454/507ivo://CDS.VizieR/J/MNRAS/454/507doi:10.26093/cds/vizier.74540507CDSMacfarlane S.A.Toma R.Ramsay G.Groot P.J.Woudt P.A.Drew J.E.,Barentsen G.Eisloffel J.2024-08-15T20:16:23Z2016-09-16T07:57:30ZCDS support team

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

cds-question@unistra.frsurveysmilky-way-galaxyvariable-starsphotometryWe present the goals, strategy and first results of the OmegaWhite survey: a wide-field high-cadence g-band synoptic survey which aims to unveil the Galactic population of short-period variable stars (with periods <80min), including ultracompact binary star systems and stellar pulsators. The ultimate goal of OmegaWhite is to cover 400deg^2^ along the Galactic plane reaching a depth of g=21.5mag (10{sigma}), using OmegaCam on the VLT Survey Telescope (VST). The fields are selected to overlap with surveys such as the Galactic Bulge Survey and the VST Photometric H{alpha} Survey of the Southern Galactic Plane for multiband colour information. Each field is observed using 38 exposures of 39s each, with a median cadence of ~2.7min for a total duration of two hours. Within an initial 26deg^2^, we have extracted the light curves of 1.6 million stars, and have identified 613 variable candidates which satisfy our selection criteria. Furthermore, we present the light curves and statistical properties of 20 sources which have the highest likelihood of being variable stars. One of these candidates exhibits the colours and light-curve properties typically associated with ultracompact AM CVn binaries, although its spectrum exhibits weak Balmer absorption lines and is thus not likely to be such a binary system. We also present follow-up spectroscopy of five other variable candidates, which identifies them as likely low-amplitude {delta} Sct pulsating stars.2015MNRAS.454..507Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/454/507CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/MNRAS/429/385 : Short-period variables near Galactic Centre (Matsunaga+ 2013)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/454/507https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/454/507http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/454/507https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/454/507https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/454/507http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/454/507GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/454/507/tablea2 (Parameters of the 613 variable candidates (selected using n=15))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/454/507/tablea2?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/454/507/tablea2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/454/507/tablea2?GETtext/xml+votable180.050000true122.8514167-29.9730.0055555555555555565/9943 9948-9950 10112 10114 6/39765-39767 39769-39771 39781-39783 39785 39787-39789 39791 39804-39805 39877 39879 39888-39890 40105-40107https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/454/507?format=asciiOpticaldefaultJ/MNRAS/454/507/tablea2Parameters of the 613 variable candidates (selected using n=15)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintOWOW designation (JHHMMSS.ss+DDMMSS.s)meta.id;meta.maincharRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainPLSLomb-Scargle period of the highest peak in the periodogrammintime.periodfloatlog10(FAP)False alarm probability (FAP) of the highest peak in the periodogramstat.fit.goodnessfloatOWgmagOW calibrated g-band magnitudemagphot.mag;em.opt.Bfloate_OWgmagrms uncertainty on OWgmagmagstat.error;phot.magfloatg-r? VPHAS+ g-r colour indexmagphot.color;em.opt.B;em.opt.Rfloatnullableu-g? VPHAS+ u-g colour indexmagphot.color;em.opt.U;em.opt.BfloatnullableSimbadSimbad column added by the CDSmeta.ref.urlchar