2009/05/28 by Norio Narita, Teruyuki Hirano, Bun'ei Sato +7 · 2 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Eccentricity (behavior) #Exoplanet #History and Developments in Astronomy #Orbital eccentricity #Orbital elements #Orbital mechanics #Planetary system #Stellar, planetary, and galactic studies #Subaru Telescope #Transit (satellite) #astro-ph.EP #astro-ph.SR
paper · pdf · doi:10.1093/pasj/61.5.991
16 pages, 3 figures, 3 tables, PASJ accepted
arxiv created 2009/05/28 · openalex publication_date 2009/10/25 · arxiv updated 2015/05/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Abstract We present an improved measurement of the Rossiter–McLaughlin effect for the exoplanetary system HD 17156, based on radial-velocity data gathered with the Subaru 8.2-m telescope throughout the planetary transit of UT 2008 November 7. The data allow for a precise and independent determination of the projected spin-orbit angle of this system: λ = 10\rlap^∘\hskip.5pt.\hskip1pt0 ± 5\rlap^∘\hskip.5pt.\hskip1pt1. This result supersedes the previous claim of λ= 62^∘ ± 25^∘ by Narita et al. (2008, PASJ, 60, L1), which was based on lower-precision data with poor statistics. Thus the stellar spin and planetary orbital axes of the HD 17156 system are likely to be well-aligned, despite the planet’s large orbital eccentricity suggesting a history of strong dynamical interactions.