Spin-Orbit Misalignments of Three Jovian Planets via Doppler Tomography
Abstract
We present measurements of the spin-orbit misalignments of the hot Jupiters HAT-P-41 b and WASP-79 b, and the aligned warm Jupiter Kepler-448 b. We obtain these measurements with Doppler tomography, where we spectroscopically resolve the line profile perturbation during the transit due to the Rossiter-McLaughlin effect. We analyze time series spectra obtained during portions of five transits of HAT-P-41 b, and find a value of the spin-orbit misalignment of λ =-{22.1}-6.0{+0.8^\circ }. We reanalyze the radial velocity Rossiter-McLaughlin data on WASP-79 b obtained by Addison et al. using Doppler tomographic methodology. We measure λ =-{99.1}-3.9{+4.1^\circ }, consistent with but more precise than the value found by Addison et al. For Kepler-448 b we perform a joint fit to the Kepler light curve, Doppler tomographic data, and a radial velocity data set from Lillo-Box et al. We find an approximately aligned orbit (λ =-{7.1}-2.8{+4.2^\circ }), in agreement with the value found by Bourrier et al. Through analysis of the Kepler light curve we measure a stellar rotation period of {P}{rot}=1.27+/- 0.11 days, and use this to argue that the full three-dimensional spin-orbit misalignment is small, \psi ∼ 0^\circ .
Based in part on observations obtained with the Hobby-Eberly Telescope, which is a joint project of the University of Texas at Austin, the Pennsylvania State University, Stanford University, Ludwig-Maximilians-Universität München, and Georg-August-Universität Göttingen.- Publication:
-
The Astronomical Journal
- Pub Date:
- October 2017
- DOI:
- 10.3847/1538-3881/aa8462
- arXiv:
- arXiv:1708.01291
- Bibcode:
- 2017AJ....154..137J
- Keywords:
-
- line: profiles;
- planetary systems;
- planets and satellites: individual:: HAT-P-41 b;
- Kepler-448 b;
- WASP-79 b;
- techniques: spectroscopic;
- Astrophysics - Earth and Planetary Astrophysics
- E-Print:
- Accepted for publication in AJ. 16 pages, 8 figures