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Discovery of a Rare Late-type, Low-mass Wolf-Rayet Star in the LMC

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dc.abstract.enWe report the serendipitous discovery of an object, UVQS J060819.93-715737.4, with a spectrum dominated by extremely intense, narrow C II emission lines. The spectrum is similar to those of the very rare, late-type [WC11] low-mass Wolf-Rayet stars. Despite the recognition of these stars as a distinct class decades ago, there remains barely a handful of Galactic members, all of which are also planetary-nebula central stars. Although no obvious surrounding nebulosity is present in J0608, [O II], [N II], and [S II] emission suggest the presence of an inconspicuous, low-excitation nebula. There is low-amplitude incoherent photometric variability on timescales of days to years, as well as numerous prominent P Cygni profiles, implying mass loss. There are indications of a binary companion. The star is located on the outskirts of the LMC, and the observed radial velocity (˜+250 km s<SUP>-1</SUP>) and proper motion strongly suggest membership. If indeed an LMC member, this is the first extragalactic late [WC] star, and the first with an accurately determined luminosity, as the Galactic examples are too distant for precise parallax determinations. A high-quality, broad-coverage spectrum of the prototype of the late [WC] class, CPD -56° 8032, is also presented. We discuss different excitation mechanisms capable of producing the great strength of the C II emission. Numerous autoionizing levels of C II are definitely populated by processes other than dielectronic recombination. Despite the spectacular emission spectra, observational selection makes objects such as these difficult to discover. Members of the [WC11] class may in fact be considerably more common than the handful of previously known late [WC] stars.
dc.affiliationUniwersytet Warszawski
dc.contributor.authorMargon, Bruce
dc.contributor.authorManea, Catherine
dc.contributor.authorWilliams, Robert
dc.contributor.authorBond, Howard E.
dc.contributor.authorProchaska, J. Xavier
dc.contributor.authorSzymański, Michał
dc.contributor.authorMorrell, Nidia
dc.date.accessioned2024-01-24T21:54:38Z
dc.date.available2024-01-24T21:54:38Z
dc.date.copyright2019-11-28
dc.date.issued2020
dc.description.accesstimeBEFORE_PUBLICATION
dc.description.financePublikacja bezkosztowa
dc.description.number2
dc.description.versionORIGINAL_AUTHOR
dc.description.volume888
dc.identifier.doi10.3847/1538-4357/AB5E78
dc.identifier.issn0004-637X
dc.identifier.urihttps://repozytorium.uw.edu.pl//handle/item/104974
dc.identifier.weblinkhttp://adsabs.harvard.edu/abs/2020ApJ...888...54M
dc.languageeng
dc.pbn.affiliationastronomy
dc.relation.ispartofAstrophysical Journal
dc.relation.pages54
dc.rightsOther
dc.sciencecloudnosend
dc.titleDiscovery of a Rare Late-type, Low-mass Wolf-Rayet Star in the LMC
dc.typeJournalArticle
dspace.entity.typePublication