2021/12/13 by Amaury H. M. J. Triaud, A. H. M. J. Triaud, Matthew R. Standing +54 · 1 citation
Physics and Astronomy · #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Astrophysics and Star Formation Studies #Binary number #Circumbinary planet #Eclipse #Exoplanet #Physics #Planet #Radial velocity #Spectral line #Spectrograph #Stars #Stellar, planetary, and galactic studies #astro-ph.EP #astro-ph.SR
paper · pdf · doi:10.1093/mnras/stab3712
under review at MNRAS, 7 pages, 4 figures, all RV data in appendix
arxiv created 2021/12/13 · openalex publication_date 2021/12/22 · arxiv updated 2022/02/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
ABSTRACT The radial velocity method is amongst the most robust and most established means of detecting exoplanets. Yet, it has so far failed to detect circumbinary planets despite their relatively high occurrence rates. Here, we report velocimetric measurements of Kepler-16A, obtained with the SOPHIE spectrograph, at the Observatoire de Haute-Provence’s 193cm telescope, collected during the BEBOP survey for circumbinary planets. Our measurements mark the first radial velocity detection of a circumbinary planet, independently determining the mass of Kepler-16 (AB) b to be 0.313 ± 0.039 \rm M\rm Jup, a value in agreement with eclipse timing variations. Our observations demonstrate the capability to achieve photon-noise precision and accuracy on single-lined binaries, with our final precision reaching \rm 1.5~m s-1 on the binary and planetary signals. Our analysis paves the way for more circumbinary planet detections using radial velocities which will increase the relatively small sample of currently known systems to statistically relevant numbers, using a method that also provides weaker detection biases. Our data also contain a long-term radial velocity signal, which we associate with the magnetic cycle of the primary star.