J/A+A/674/A88ivo://CDS.VizieR/J/A+A/674/A88doi:10.26093/cds/vizier.36740088CDSDsilva K.Shenar T.Sana H.Marchant P.2024-11-28T20:04:03Z2023-06-07T08:24:17ZCDS support team

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

cds-question@unistra.frvariable-starsvisible-astronomyspectroscopyMassive stars are powerful cosmic engines. In the phases immediately preceding core-collapse, massive stars in the Galaxy with Mi>20M_{sun}_ may appear as classical Wolf-Rayet (WR) stars. As the final contribution of a homogeneous RV survey, this work constrains the multiplicity properties of northern Galactic late-type nitrogen-rich Wolf-Rayet (WNL) stars. We compare their intrinsic binary fraction and orbital period distribution to the carbon-rich (WC) and early-type nitrogen-rich (WNE) populations from previous works. We obtained high-resolution spectra of the complete magnitude-limited sample of 11 Galactic WNL stars with the Mercator telescope on the island of La Palma. We used cross-correlation to measure relative RVs and flagged binary candidates based on the peak-to-peak RV dispersion. By using Monte Carlo sampling and a Bayesian framework, we computed the three-dimensional likelihood and one-dimensional posteriors for the upper period cut-off (logP_max_^WNL^), power-law index ({PI}^WNL^), and intrinsic binary fraction (f_int_^WNL^). Adopting a threshold C of 50km/s, we derived f_obs_^WNL^=0.36+/-0.15. Our Bayesian analysis produces f_int_^WNL^=0.42_-0.17_^+0.15^, {PI}^WNL^=-0.70_-1.02_^+0.73^ and logP_max_^WNL^=4.90_-3.40_^+0.09^ for the parent WNL population. The combined analysis of the Galactic WN population results in f_int_^WN^=0.52_-0.12_^+0.14^, {PI}^WN^=-0.99_-0.50_^+0.57^ and logP_max_^WN^=4.99+_1.11_^+0.00^. The observed period distribution of Galactic WN and WC binaries from the literature is in agreement with what is found. The period distribution of Galactic WN binaries peaks at P~1-10d and that of the WC population at P~5000d. This shift cannot be reconciled by orbital evolution due to mass loss or mass transfer. At long periods, the evolutionary sequence O (->LBV) -> WN -> WC seems feasible. The high frequency of short-period WN binaries compared to WC binaries suggests that they either tend to merge or that the WN components in these binaries rarely evolve into WC stars in the Galaxy.2023A&A...674A..88Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/674/A88CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/664/A93 : Northern WNE star spectra (Dsilva+, 2022)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/674/A88https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/674/A88http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/674/A88https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/674/A88https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/674/A88http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/674/A88GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/674/A88/table1 (Eleven WNL stars in our RV monitoring campaign)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/674/A88/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/674/A88/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/674/A88/table1?GETtext/xml+votable180.050000true271.3572083-23.00563890.005555555555555556Associated datahttps://cdsarc.cds.unistra.fr/assocdata/?obs_collection=J/A+A/674/A886/14255 14259 14302 14315 14631 14649 15506 28916 30231 30245 32070https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/674/A88?format=asciiOpticaldefaultJ/A+A/674/A88/table1Eleven WNL stars in our RV monitoring campaignSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintStarStar namemeta.id;meta.maincharRAJ2000Simbad right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Simbad declination (J2000)pos.eq.dec;meta.mainNspNumber of spectrameta.numberintTimeTime baseline of coveragedtime.epochintS/NAverage S/N per resolution element at 5100{AA}stat.snrintJ/A+A/674/A88/listList of fits spectrarecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintStarStar namemeta.id;meta.maincharNxNumber of pixels along X-axismeta.numberintObs.dateObservation datestime.epoch;obsnullableloglambdaWavelengthlog(0.1nm)em.wldoublesizeSize of FITS fileKibytephys.size;meta.fitsintspShow the spectrummeta.ref.urlcharFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharTitleTitle of the FITS filemeta.title;meta.fitschar