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dc.creatorSkuladottir, A.en_US
dc.creatorTolstoy, E.en_US
dc.creatorSalvadori, S.en_US
dc.creatorHill, V.en_US
dc.creatorPettini, M.en_US
dc.creatorShetrone, M. D.en_US
dc.creatorStarkenburg, E.en_US
dc.date.accessioned2016-04-22T19:43:12Z
dc.date.available2016-04-22T19:43:12Z
dc.date.issued2015-02en
dc.identifierdoi:10.15781/T2VR3J
dc.identifier.citationSkúladóttir, Á., Eline Tolstoy, Stefania Salvadori, Vanessa Hill, Max Pettini, Matthew D. Shetrone, and Else Starkenburg. >The first carbon-enhanced metal-poor star found in the Sculptor dwarf spheroidal.> Astronomy & Astrophysics, Vol. 574 (Feb., 2015): A129.en_US
dc.identifier.issn0004-6361en_US
dc.identifier.urihttp://hdl.handle.net/2152/34278
dc.description.abstractThe origin of carbon-enhanced metal-poor (CEMP) stars and their possible connection with the chemical elements produced by the first stellar generation is still highly debated. In contrast to the Galactic halo, not many CFMP stars have been found in the dwarf spheroidal galaxies around the Milky Way. Here we present detailed abundances from ESO VET/IVES high resolution spectroscopy for ET0097, the first CEMP star found in the Sculptor dwarf spheroidal, which is one of the best studied dwarf galaxies in the Local Group, This star has [Fe/H] = 2.03 +/- 0.10, [C/Fe] = 0.51 +/- 0.10 and [N/Fe]) = 1.18 +/- . 0.20, which is the first nitrogen measurement in this galaxy. The traditional definition of CEIVIP Stars is [C/Fe] >= 0.70, but taking into account that this luminous red giant branch star has undergone mixing, it was intrinsically less nitrogen enhanced and more carbon rich when it was formed, and so it falls under the definition of CEMP stars, as proposed by Aoki et al. (2007. ApJ, 655. 492) to account for this effect. By making corrections for this mixing. we conclude that the star had EC/Fel 0.8 during its earlier evolutionary stages. Apart from the enhanced C and N abundances, ET0097 shows no peculiarities in other elements lighter than Zn. and no enhancement of the heavier neutron capture elements (Ba, La, Ce, Ncl, Sm Eu, Dy). making this a CEMP-no star. However, the star does show signs of the weak hprocess. with an overabundance of the lighter neutron-capture elements (Sr, Y, Zr). To explain the abundance pattern observed in ET0097, we explore the possibility that this star was enriched by primordial stars. In addition to the detailed abundances for ET0097. we present estimates and upper limits for C abundances in 85 other stars in Sculptor derived from UN molecular lines. including 11 stars with [Fe/H] <= -2. Combining these limits with observations horn the literature, the fraction of CEMP-no stars in Sculptor seems to be significantly lower than in the Galactic halo.en_US
dc.description.sponsorshipInternational Space Science Institute (ISSI), Bern, Switzerlanden_US
dc.description.sponsorshipNetherlands Organisation for Scientific Research (NWO), VENI 639.041.233en_US
dc.language.isoEnglishen_US
dc.rightsAdministrative deposit of works to Texas ScholarWorks: This works author(s) is or was a University faculty member, student or staff member; this article is already available through open access or the publisher allows a PDF version of the article to be freely posted online. The library makes the deposit as a matter of fair use (for scholarly, educational, and research purposes), and to preserve the work and further secure public access to the works of the University.en_US
dc.subjectstars: abundancesen_US
dc.subjectstars: individual: sculptor dwarf spheroidalen_US
dc.subjectgalaxies: abundancesen_US
dc.subjectgalaxies: dwarfen_US
dc.subjectgalaxies: evolutionen_US
dc.subjectneutron-capture elementsen_US
dc.subjectb-2-sigma(+)-x-2-sigma(+) violet systemsen_US
dc.subjecthigh-dispersion-spectrographen_US
dc.subjecteffective temperature scaleen_US
dc.subjectr-processen_US
dc.subjectelementsen_US
dc.subjectchemical-compositionsen_US
dc.subjectearly galaxyen_US
dc.subjecta(2)pi-x-2-sigma(+) reden_US
dc.subjecthomogeneous sampleen_US
dc.subjectgalactic evolutionen_US
dc.subjectastronomy & astrophysicsen_US
dc.titleThe First Carbon-Enhanced Metal-Poor Star Found In The Sculptor Dwarf Spheroidal OCR Issueen_US
dc.typeArticleen_US
dc.description.departmentAstronomyen_US
dc.identifier.doi10.1051/0004-6361/201424782en_US
dc.contributor.utaustinauthorShetrone, Matthew D.en_US
dc.relation.ispartofserialAstronomy & Astrophysicsen_US


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