Accurate fundamental parameters for 23 bright solar-type stars

H. Bruntt, T. R. Bedding, P. O. Quirion, G. Lo Curto, F. Carrier, B. Smalley, T. H. Dall, T. Arentoft, Michael Bazot, R. P. Butler

    Research output: Contribution to journalArticle

    Abstract

    We combine results from interferometry, asteroseismology and spectroscopy to determine accurate fundamental parameters of 23 bright solar-type stars, from spectral type F5 to K2 and luminosity classes III-V. For some stars we can use direct techniques to determine the mass, radius, luminosity and effective temperature, and we compare with indirect methods that rely on photometric calibrations or spectroscopic analyses. We use the asteroseismic information available in the literature to infer an indirect mass with an accuracy of 4-15 per cent. From indirect methods we determine luminosity and radius to 3 per cent. We find evidence that the luminosity from the indirect method is slightly overestimated (≈ 5 per cent) for the coolest stars, indicating that their bolometric corrections (BCs) are too negative. For Teff we find a slight offset of -40 ± 20 K between the spectroscopic method and the direct method, meaning the spectroscopic temperatures are too high. From the spectroscopic analysis we determine the detailed chemical composition for 13 elements, including Li, C and O. The metallicity ranges from [Fe/H]=-1.7 to +0.4, and there is clear evidence for α-element enhancement in the metal-poor stars. We find no significant offset between the spectroscopic surface gravity and the value from combining asteroseismology with radius estimates. From the spectroscopy we also determine v sin i and we present a new calibration of macroturbulence and microturbulence. From the comparison between the results from the direct and spectroscopic methods we claim that we can determine Teff, log and [Fe/H] with absolute accuracies of 80 K, 0.08 and 0.07 dex. Photometric calibrations of Strömgren indices provide accurate results for Teff and [Fe/H] but will be more uncertain for distant stars when interstellar reddening becomes important. The indirect methods are important to obtain reliable estimates of the fundamental parameters of relatively faint stars when interferometry cannot be used. This paper is the first to compare direct and indirect methods for a large sample of stars, and we conclude that indirect methods are valid, although slight corrections may be needed.

    Original languageEnglish (US)
    Pages (from-to)1907-1923
    Number of pages17
    JournalMonthly Notices of the Royal Astronomical Society
    Volume405
    Issue number3
    DOIs
    StatePublished - Jul 1 2010

    Fingerprint

    stars
    luminosity
    asteroseismology
    radii
    interferometry
    calibration
    interstellar extinction
    cool stars
    spectroscopic analysis
    estimates
    spectroscopy
    metallicity
    method
    parameter
    chemical composition
    gravitation
    temperature
    augmentation
    metals
    gravity

    Keywords

    • Stars: abundances
    • Stars: fundamental parameters
    • Stars: solar-type
    • Techniques: spectroscopic

    ASJC Scopus subject areas

    • Astronomy and Astrophysics
    • Space and Planetary Science

    Cite this

    Bruntt, H., Bedding, T. R., Quirion, P. O., Lo Curto, G., Carrier, F., Smalley, B., ... Butler, R. P. (2010). Accurate fundamental parameters for 23 bright solar-type stars. Monthly Notices of the Royal Astronomical Society, 405(3), 1907-1923. https://doi.org/10.1111/j.1365-2966.2010.16575.x

    Accurate fundamental parameters for 23 bright solar-type stars. / Bruntt, H.; Bedding, T. R.; Quirion, P. O.; Lo Curto, G.; Carrier, F.; Smalley, B.; Dall, T. H.; Arentoft, T.; Bazot, Michael; Butler, R. P.

    In: Monthly Notices of the Royal Astronomical Society, Vol. 405, No. 3, 01.07.2010, p. 1907-1923.

    Research output: Contribution to journalArticle

    Bruntt, H, Bedding, TR, Quirion, PO, Lo Curto, G, Carrier, F, Smalley, B, Dall, TH, Arentoft, T, Bazot, M & Butler, RP 2010, 'Accurate fundamental parameters for 23 bright solar-type stars', Monthly Notices of the Royal Astronomical Society, vol. 405, no. 3, pp. 1907-1923. https://doi.org/10.1111/j.1365-2966.2010.16575.x
    Bruntt H, Bedding TR, Quirion PO, Lo Curto G, Carrier F, Smalley B et al. Accurate fundamental parameters for 23 bright solar-type stars. Monthly Notices of the Royal Astronomical Society. 2010 Jul 1;405(3):1907-1923. https://doi.org/10.1111/j.1365-2966.2010.16575.x
    Bruntt, H. ; Bedding, T. R. ; Quirion, P. O. ; Lo Curto, G. ; Carrier, F. ; Smalley, B. ; Dall, T. H. ; Arentoft, T. ; Bazot, Michael ; Butler, R. P. / Accurate fundamental parameters for 23 bright solar-type stars. In: Monthly Notices of the Royal Astronomical Society. 2010 ; Vol. 405, No. 3. pp. 1907-1923.
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    AU - Bedding, T. R.

    AU - Quirion, P. O.

    AU - Lo Curto, G.

    AU - Carrier, F.

    AU - Smalley, B.

    AU - Dall, T. H.

    AU - Arentoft, T.

    AU - Bazot, Michael

    AU - Butler, R. P.

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