Accurate and precise radius estimates of transiting exoplanets are critical for understanding their compositions and formation mechanisms. To know the planet, we must know the host star in as much detail as possible. We present complete results for planet-candidate hosts from the K2-HERMES survey, which uses the HERMES multi-object spectrograph on the Anglo-Australian Telescope to obtain R ∼ 28000 spectra for more than 30 000 K2 stars. We present complete host-star parameters and planet-candidate radii for 224 K2 candidate planets from C1-C13. Our results cast severe doubt on 30 K2 candidates, as we derive unphysically large radii, larger than 2R Jup. This work highlights the importance of obtaining accurate, precise, and self-consistent stellar parameters for ongoing large planet search programs-something that will only become more important in the coming years, as TESS begins to deliver its own harvest of exoplanets.
Bibliographical noteThis article has been accepted for publication in Monthly Notices of the Royal Astronomical Society, Volume 496, Issue 1, July 2020, Pages 851–863, https://doi.org/10.1093/mnras/staa1528. Copyright 2020 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
- planets and satellites: fundamental parameters
- stars: fundamental parameters
- techniques: spectroscopic