The distribution of stellar obliquities provides critical insight into the formation and evolution pathways of exoplanets. In the past decade, it was found that hot stars hosting hot Jupiters are more likely to have high obliquities than cool stars, but it is not clear whether this trend exists only for hot Jupiters or holds for other types of planets. In this work, we extend the study of the obliquities of hot (6250–7000 K) stars with transiting super-Earth-sized and sub-Neptune-sized planets. We constrain the obliquity distribution based on measurements of the stars’ projected rotation velocities. Our sample consists of 170 TESS and Kepler planet-hosting stars and 180 control stars chosen to have indistinguishable spectroscopic characteristics. In our analysis, we find evidence suggesting that the planet hosts have a systematically higher
The orientation between a star’s spin axis and a planet’s orbital plane provides valuable information about the system’s formation and dynamical history. For non-transiting planets at wide separations, true stellar obliquities are challenging to measure, but lower limits on spin–orbit orientations can be determined from the difference between the inclination of the star’s rotational axis and the companion’s orbital plane (Δ
- NSF-PAR ID:
- 10402156
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astronomical Journal
- Volume:
- 165
- Issue:
- 4
- ISSN:
- 0004-6256
- Format(s):
- Medium: X Size: Article No. 164
- Size(s):
- Article No. 164
- Sponsoring Org:
- National Science Foundation
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