J/PAZh/36/281ivo://CDS.VizieR/J/PAZh/36/281CDSArkhipova V.P.Ikonnikova N.P.2017-06-27T06:38:38Z2011-10-24T15:49:30ZCDS support team

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

cds-question@unistra.frsupergiant-starsvisible-astronomyWide-band photometryWe present new photometric data and analyze long-term UBV observations of three candidates for protoplanetary nebulae - F supergiants with infrared excesses at high Galactic latitudes -IRAS 18095+2704, IRAS 19386+0155, and IRAS 19500-1709. All these stars exhibit quasi-periodic low-amplitude variations caused by pulsations against the background of long-term brightness trends. For IRAS 18095+2704 = V887 Her, we have found a pulsation period of 109 days and revealed a linear brightness trend - the star brightens at constant (within the limits of the measurement errors) yearly mean color indices. The light curve of IRAS 19386+0155 = V1648 Aql in 2000-008 is represented by a wave with a fundamental period of 102 days whose modulation with a close period of 98 days leads to variations with a variable amplitude. V1648 Aql also shows a systematic rise in V brightness along with a reddening. IRAS 19500-1709 = V5112 Sgr exhibits irregular pulsations with periods of 39 and 47 days. The long-term variability component of V5112 Sgr may indicate that the star is binary.2010PAZh...36..281Ahttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/PAZh/36/281CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/PAZh/36/281https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/PAZh/36/281http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/PAZh/36/281https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/PAZh/36/281https://vizier.iucaa.in/viz-bin/votable?-source=J/PAZh/36/281http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/PAZh/36/281GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tap3.322582951404819e-19 3.852589004194616e-19OpticaldefaultJ/PAZh/36/281/table4V5112 Sgr UBV-observations in 2000-2008recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJDJulian datedtime.epochintVmagV magnitudemagphot.mag;em.opt.VfloatB-VB-V color indexmagphot.color;em.opt.B;em.opt.VfloatU-BU-B color indexmagphot.color;em.opt.U;em.opt.BfloatJ/PAZh/36/281/table2V887 Her UBV-observations in 2000-2008recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJDJulian datedtime.epochintVmagV magnitudemagphot.mag;em.opt.VfloatB-VB-V color indexmagphot.color;em.opt.B;em.opt.VfloatU-BU-B color indexmagphot.color;em.opt.U;em.opt.BfloatJ/PAZh/36/281/table3V1648 Aql UBV-observations in 2000-2008VmagV magnitudemagphot.mag;em.opt.VfloatB-VB-V color indexmagphot.color;em.opt.B;em.opt.VfloatU-BU-B color indexmagphot.color;em.opt.U;em.opt.BfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJDJulian datedtime.epochint