A Misaligned Prograde Orbit for Kepler-13 Ab via Doppler Tomography

Abstract

Transiting planets around rapidly rotating stars are not amenable to precise radial velocity observations, such as are used for planet candidate validation, as they have wide, rotationally broadened stellar lines. Such planets can, however, be observed using Doppler tomography, wherein the stellar absorption line profile distortions during transit are spectroscopically resolved. This allows the validation of transiting planet candidates and the measurement of the stellar spin-planetary orbit (mis)alignment, an important statistical probe of planetary migration processes. We present Doppler tomographic observations which provide a direct confirmation of the hot Jupiter Kepler-13 Ab, and also show that the planet has a prograde, misaligned orbit, with lambda = 58.6 +/- 2.0 degrees. Our measured value of the spin-orbit misalignment is in significant disagreement with the value of lambda = 23 +/- 4 degrees previously measured by Barnes et al. (2011) from the gravity-darkened Kepler lightcurve. We also place an upper limit of 0.75 solar masses (95% confidence) on the mass of Kepler-13 C, the spectroscopic companion to Kepler-13 B, the proper motion companion of the planet host star Kepler-13 A.

14 pages, 12 figures. Accepted for publication in ApJ

References in corpus (9)

• The generalised Lomb-Scargle periodogram. A new formalism for the floating-mean and Keplerian periodograms
• Dynamical Outcomes of Planet-Planet Scattering
• Detection Limits from the McDonald Observatory Planet Search Program
• The spin axes orbital alignment of both stars within the eclipsing binary system V1143Cyg using the Rossiter-McLaughlin effect
• Tidal Dissipation and Obliquity Evolution in Hot Jupiter Systems
• Multisite campaign on the open cluster M67. II. Evidence for solar-like oscillations in red giant stars
• The BANANA project. V. Misaligned and precessing stellar rotation axes in CV Velorum
• Analysis of spin-orbit alignment in the WASP-32, WASP-38, and HAT-P-27/WASP-40 systems
• SOPHIE velocimetry of Kepler transit candidates VI. An additional companion in the KOI-13 system

Cited by in corpus (16)

• Kepler-432: a red giant interacting with one of its two long period giant planets
• A high binary fraction for the most massive close-in giant planets and brown dwarf desert members
• KELT-17b: A hot-Jupiter transiting an A-star in a misaligned orbit detected with Doppler tomography
• Visible-light Phase Curves from the Second Year of the TESS Primary Mission
• Spin-Orbit Angles of Kepler-13Ab and HAT-P-7b from Gravity-Darkened Transit Light Curves
• KELT-19Ab: A P~4.6 Day Hot Jupiter Transiting a Likely Am Star with a Distant Stellar Companion
• H-alpha and Ca II Infrared Triplet Variations During a Transit of the 23 Myr Planet V1298 Tau c
• TESS Delivers Five New Hot Giant Planets Orbiting Bright Stars from the Full Frame Images
• Spin-Orbit Misalignments of Three Jovian Planets via Doppler Tomography
• Gravity-Darkening Analysis of Misaligned Hot Jupiter MASCARA-4 b
• Spin-Orbit Misalignment and Precession in the Kepler-13Ab Planetary System
• The clockwork is moving on -- a combined analysis of TESS and Kepler measurements of Kepler-13Ab
• Rapid rotators revisited: absolute dimensions of KOI-13
• Nodal Precession of WASP-33b for Eleven Years by Doppler Tomographic and Transit Photometric Observations
• Rapidly rotating stars and their transiting planets: KELT-17b, KELT-19Ab, and KELT-21b in the CHEOPS and TESS era
• Exoplanet System Kepler-2 with comparisons to Kepler-1 and 13