The masses of retired A stars with asteroseismology: Kepler and K2 observations of exoplanet hosts

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review

DOI

    Thomas S. H. North, Univ Birmingham, University of Birmingham, Sch Phys & Astron, Tiago L. Campante, Univ Birmingham, University of Birmingham, Sch Phys & Astron, Georg August Univ Gottingen, University of Gottingen, Inst Astrophys,
  • Andrea Miglio
  • Guy R. Davies, Univ Birmingham, University of Birmingham, Sch Phys & Astron, Samuel K. Grunblatt, Univ Hawaii, University of Hawaii System, Inst Astron, Daniel Huber, Univ Hawaii, University of Hawaii System, Inst Astron, Univ Sydney, University of Sydney, Sch Phys, SIfA, SETI Inst, James S. Kuszlewicz, Univ Birmingham, University of Birmingham, Sch Phys & Astron,
  • Mikkel N. Lund
  • Benjamin F. Cooke, William J. Chaplin, Univ Birmingham, University of Birmingham, Sch Phys & Astron

We investigate the masses of 'retired A stars' using asteroseismic detections on seven low-luminosity red-giant and sub-giant stars observed by the NASA Kepler and K2 missions. Our aim is to explore whether masses derived from spectroscopy and isochrone fitting may have been systematically overestimated. Our targets have all previously been subject to long-term radial velocity observations to detect orbiting bodies, and satisfy the criteria used by Johnson et al. to select survey stars which may have had A-type (or early F-type) main-sequence progenitors. The sample actually spans a somewhat wider range in mass, from approximate to 1 M-circle dot up to approximate to 1.7 M-circle dot. Whilst for five of the seven stars the reported discovery mass from spectroscopy exceeds the mass estimated using asteroseismology, there is no strong evidence for a significant, systematic bias across the sample. Moreover, comparisons with other masses from the literature show that the absolute scale of any differences is highly sensitive to the chosen reference literature mass, with the scatter between different literature masses significantly larger than reported error bars. We find that any mass difference can be explained through use of different constraints during the recovery process. We also conclude that underestimated uncertainties on the input parameters can significantly bias the recovered stellar masses, which may have contributed to the controversy on the mass scale for retired A stars.

Original languageEnglish
JournalRoyal Astronomical Society. Monthly Notices
Volume472
Issue number2
Pages (from-to)1866-1878
Number of pages13
ISSN0035-8711
DOIs
StatePublished - Dec 2017

    Research areas

  • asteroseismology, techniques: photometric, stars: evolution, stars: fundamental parameters, RED-GIANT STARS, SOLAR-LIKE OSCILLATIONS, STELLAR EVOLUTION, BOLOMETRIC CORRECTIONS, MAGNETIC-FIELDS, PLANET, PARAMETERS, MISSION, CORES, COMPANIONS

See relations at Aarhus University Citationformats

ID: 119462711