J/A+A/607/A78ivo://CDS.VizieR/J/A+A/607/A78doi:10.26093/cds/vizier.36070078CDSKaminski T.Menten K.M.Tylenda R.Karakas A.Belloche A.Patel N.A.2017-11-28T08:21:45Z2017-11-17T09:21:14ZCDS support team

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

cds-question@unistra.frnovaespectroscopyCK Vulpeculae (CK Vul) is an enigmatic star whose outburst was observed in 1670-72. A stellar-merger event was proposed to explain its ancient eruption. We aim to investigate the composition of the molecular gas recently discovered in the remnant of CK Vul. Deriving the chemical, elemental, and isotopic composition is crucial for identifying the nature of the object and obtaining clues on its progenitor(s). We observed millimeter and submillimeter-wave spectra of CK Vul using the IRAM 30m and APEX telescopes. Radiative-transfer modeling of the observed molecular features was performed to yield isotopic ratios for various elements. The spectra of CK Vul reveal a very rich molecular environment of low excitation (T_ex_~<12K). Atomic carbon and twenty seven different molecules, including two ions, were identified. They range from simple diatomic to complex polyatomic species of up to seven atoms large. The chemical composition of the molecular gas is indicative of carbon and nitrogen-driven chemistry but oxides are also present. Additionally, the abundance of F may be enhanced. The spectra are rich in isotopologues that are very rare in most known sources. All stable isotopes of C, N, O, Si, and S are observed and their isotopic ratios are derived. The composition of the remnant's molecular gas is most peculiar and gives rise to a very unique millimeter and submillimeter spectrum. The observation of ions and complex molecules suggests the presence of a photoionizing source but its nature (a central star or shocks) remains unknown. The elemental and isotopic composition of the gas cannot be easily reconciled with standard nucleosynthesis but processing in hot CNO cycles and partial He burning can explain most of the chemical peculiarities. The isotopic ratios of CK Vul are remarkably close to those of presolar nova grains but the link of Nova 1670 to objects responsible for these grains is unclear.2017A&A...607A..78Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/607/A78CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/607/A78https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/607/A78http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/607/A78https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/607/A78https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/607/A78http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/607/A78GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/607/A78/list (List of fits spectra)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/607/A78/list?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/607/A78/list?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/607/A78/list?GETtext/xml+votable180.050000true296.9083127.313310.0055555555555555566/14409https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/607/A78?format=asciiOpticaldefaultJ/A+A/607/A78/listList of fits spectradFreqFrequency resolutionHzspect.resolutionintspShow the spectrummeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right Ascension of center (J2000)degpos.eq.ra;meta.mainDEJ2000Declination of center (J2000)degpos.eq.dec;meta.mainNxNumber of pixels along X-axismeta.numberintObs.DateObservation date (YYYY-MM-DDThh:mm:ss.sss)time.epoch;obscharbFreqLower value of frequency intervalHzem.freq;stat.mindoubleBFreqUpper value of frequency intervalHzem.freq;stat.maxdoublesizeSize of FITS fileKibytephys.size;meta.fitsintFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharTitleTitle of the FITS filemeta.title;meta.fits