J/ApJ/812/133ivo://CDS.VizieR/J/ApJ/812/133doi:10.26093/cds/vizier.18120133CDSSchaefer B.E.Edwards Z.I.2017-06-12T08:25:25Z2016-03-02T14:39:33ZCDS support team

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

cds-question@unistra.frinfrared-photometryvisible-astronomybroad-band-photometryplanetary-nebulaeUp until around 1980, the Stingray was an ordinary B1 post-AGB star, but then it suddenly sprouted bright emission lines like in a planetary nebula (PN), and soon after this the Hubble Space Telescope (HST) discovered a small PN around the star, so apparently we have caught a star in the act of ionizing a PN. We report here on a well-sampled light curve from 1889 to 2015, with unique coverage of the prior century plus the entire duration of the PN formation plus three decades of its aftermath. Surprisingly, the star anticipated the 1980s ionization event by declining from B=10.30 in 1889 to B=10.76 in 1980. Starting in 1980, the central star faded fast, at a rate of 0.20mag/yr, reaching B=14.64 in 1996. This fast fading is apparently caused by the central star shrinking in size. From 1994 to 2015, the V-band light curve is almost entirely from the flux of two bright [OIII] emission lines from the unresolved nebula, and it shows a consistent decline at a rate of 0.090mag/yr. This steady fading (also seen in the radio and infrared) has a timescale equal to that expected for ordinary recombination within the nebula, immediately after a short-duration ionizing event in the 1980s. We are providing the first direct measure of the rapidly changing luminosity of the central star on both sides of a presumed thermal pulse in 1980, with this providing a strong and critical set of constraints, and these are found to sharply disagree with theoretical models of PN evolution.2015ApJ...812..133Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/812/133CatalogResearchIsServedByTAP VizieR generic servicerelated-toB/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-2014)B/gcvs : General Catalogue of Variable Stars (Samus+ 2007-2013)II/336 : AAVSO Photometric All Sky Survey (APASS) DR9 (Henden+, 2016)II/297 : AKARI/IRC mid-IR all-sky Survey (ISAS/JAXA, 2010)II/264 : ASAS Variable Stars in Southern hemisphere (Pojmanski+, 2002-2005)II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)V/15 : SAO and Supplementary Data (Ochsenbein 1980)J/MNRAS/431/2 : H{alpha} fluxes of Galactic planetary nebulae (Frew+, 2013)J/A+A/514/A3 : Star-galaxy separation in AKARI FIS Survey (Pollo+, 2010)J/A+A/469/1221 : Sydney observatory Galactic survey (SOGS) (Fresneau+, 2007)J/MNRAS/349/793 : Galactic PNe abundances (Perinotto+, 2004)J/AcA/50/177 : All Sky Automated Survey Catalog (Pojmanski+, 2000)J/A+AS/132/13 : Planetary nebulae radial velocities (Durand+ 1998)J/A+AS/126/479 : NIR photometry of IRAS sources. III (Garcia-Lario+, 1997)J/PASP/107/846 : LSE stars, extension of Case-Hamburg surveys. (Drilling+ 1995)J/A+A/299/755 : Stellar evolution. II. Post-AGB (Bloecker+, 1995)J/A+AS/104/315 : Member of Herbig Ae/Be stellar group (The+ 1994)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/812/133https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/812/133http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/812/133https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/812/133https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/812/133http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/812/133GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapInfraredOpticaldefaultJ/ApJ/812/133/table2Stingray light curve 1889-2014BandBand (UBVg'r'i')meta.code;instr.filtercharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJDJulian date of observationdtime.epochdoubleObs.YYear of observationyrtime.epochdoublemag[9.8/15.4] Magnitude in Bandmagphot.magfloate_mag[0.01/0.3] Uncertainty in magmagstat.error;phot.magfloatr_magSource of mag (1)meta.refchar