000005504 001__ 5504
000005504 005__ 20211221143648.0
000005504 0247_ $$2DOI$$a10.1051/0004-6361/202140466
000005504 037__ $$aSCART-2021-0156
000005504 100__ $$aGebruers, S.
000005504 245__ $$aA homogeneous spectroscopic analysis of a Kepler legacy sample of dwarfs for gravity-mode asteroseismology
000005504 260__ $$c2021
000005504 520__ $$aContext. Asteroseismic modelling of the internal structure of main-sequence stars born with a convective core has so far been based on homogeneous analyses of space photometric Kepler light curves of four years in duration, to which most often incomplete inhomogeneously-deduced spectroscopic information was added to break degeneracies. Aims. Our goal is twofold: (1) to compose an optimal sample of gravity-mode pulsators observed by the Kepler space telescope for joint asteroseismic and spectroscopic stellar modelling, and (2) to provide spectroscopic parameters for its members, deduced in a homogeneous way. Methods. We assembled HERMES high-resolution optical spectroscopy at the 1.2 m Mercator telescope for 111 dwarfs, whose Kepler light curves allowed for the determination of their near-core rotation rates. Our spectroscopic information offers additional observational input to also model the envelope layers of these non-radially pulsating dwarfs. Results. We determined stellar parameters and surface abundances from atmospheric analysis with spectrum normalisation based on a new machine-learning tool. Our results suggest a systematic overestimation of metallicity ([M/H]) in the literature for the studied F-type dwarfs, presumably due to normalisation limitations caused by the dense line spectrum of these rotating stars. CNO surface abundances were found to be uncorrelated with the rotation properties of the F-type stars. For the B-type stars, we find a hint of deep mixing from C and O abundance ratios; N abundance uncertainties are too great to reveal a correlation of N with the rotation of the stars. Conclusions. Our spectroscopic stellar parameters and abundance determinations allow for the future joint spectroscopic, astrometric (Gaia), and asteroseismic modelling of this legacy sample of gravity-mode pulsators, with the aim of improving our understanding of transport processes in the core-hydrogen burning phase of stellar evolution.
000005504 594__ $$aNO
000005504 6531_ $$aasteroseismology
000005504 6531_ $$astars: variables: general
000005504 6531_ $$astars: oscillations
000005504 6531_ $$astars: fundamental parameters
000005504 6531_ $$astars: abundances
000005504 6531_ $$atechniques: spectroscopic
000005504 700__ $$aStraumit, I.
000005504 700__ $$aTkachenko, A.
000005504 700__ $$aMombarg, J.S.G.
000005504 700__ $$aPedersen, M.G.
000005504 700__ $$aVan Reeth, T.
000005504 700__ $$aLi, G.
000005504 700__ $$aLampens, P.
000005504 700__ $$aEscorza, A.
000005504 700__ $$aBowman, D.M.
000005504 700__ $$aDe Cat, P.
000005504 700__ $$aVermeylen, L.
000005504 700__ $$aBodensteiner, J.
000005504 700__ $$aRix, H.-W.
000005504 700__ $$aAerts, C.
000005504 773__ $$cA151, 1-27$$pAstronomy & Astrophysics$$v650$$y2021
000005504 8560_ $$fpeter.decat@observatoire.be
000005504 8564_ $$s2927113$$uhttps://publi2-as.oma.be/record/5504/files/Gebruers2021_AA650_A151.pdf
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000005504 905__ $$apublished in
000005504 980__ $$aREFERD