The EBLM project X. Benchmark masses, radii and temperatures for two fully convective M-dwarfs using K2
Abstract
M-dwarfs are the most abundant stars in the galaxy and popular targets for exoplanet searches. However, their intrinsic faintness and complex spectra inhibit precise characterisation. We only know of dozens of M-dwarfs with fundamental parameters of mass, radius and effective temperature characterised to better than a few per cent. Eclipsing binaries remain the most robust means of stellar characterisation. Here we present two targets from the Eclipsing Binary Low Mass (EBLM) survey that were observed with K2: EBLM J0055-00 and EBLM J2217-04. Combined with HARPS and CORALIE spectroscopy, we measure M-dwarf masses with precisions better than 5%, radii better than 3% and effective temperatures on order 1%. However, our fits require invoking a model to derive parameters for the primary star. By investigating three popular models, we determine that the model uncertainty is of similar magnitude to the statistical uncertainty in the model fits. Therefore, whilst these can be considered benchmark M-dwarfs, we caution the community to consider model uncertainty when pushing the limits of precise stellar characterisation.
Citation
Duck , A , Martin , D V , Gill , S , Armitage , T , Martínez , R R , Maxted , P F L , Sebastian , D , Sethi , R , Swayne , M I , Cameron , A C , Dransfield , G , Gaudi , B S , Gillon , M , Hellier , C , Kunovac , V , Lovis , C , McCormac , J , Pepe , F A , Pollacco , D , Sairam , L , Santerne , A , Ségransan , D , Standing , M R , Southworth , J , Triaud , A H M J & Udry , S 2023 , ' The EBLM project X. Benchmark masses, radii and temperatures for two fully convective M-dwarfs using K2 ' , Monthly Notices of the Royal Astronomical Society , vol. Advance Article , stad452 . https://doi.org/10.1093/mnras/stad452
Publication
Monthly Notices of the Royal Astronomical Society
Status
Peer reviewed
ISSN
0035-8711Type
Journal article
Rights
Copyright © 2023 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society. This work has been made available online in accordance with publisher policies or with permission. Permission for further reuse of this content should be sought from the publisher or the rights holder. This is the author created accepted manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at https://doi.org/10.1093/mnras/stad452.
Description
Funding: Support for AD was provided by NASA TESS Guest Investigator Programs for Cycle 4 (G04157) and Cycle 2(G022253). Support for DVM was provided by NASA through the NASA Hubble Fellowship grant HF2-51464 awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555. This research is also supported work funded from the European Research Council (ERC) the European Union’s Horizon 2020 research and innovation programme (grant agreement n◦803193/BEBOP). Partial support for AD, RRM, and BSG was provided by the Thomas Jefferson Chair Endowment for Discovery and Space Exploration. MIS acknowledges support from STFC grant number ST/T506175/1.Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.