14 Her: A Likely Case of Planet-Planet Scattering
Abstract
In this Letter, we measure the full orbital architecture of the two-planet system around the nearby K0 dwarf 14 Herculis. 14 Her (HD 145675, HIP 79248) is a middle-aged ( ${4.6}_{-1.3}^{+3.8}$ Gyr) K0 star with two eccentric giant planets identified in the literature from radial velocity (RV) variability and long-term trends. Using archival RV data from Keck/HIRES in concert with Gaia-Hipparcos acceleration in the proper motion vector for the star, we have disentangled the mass and inclination of the b planet to ${9.1}_{-1.1}^{+1.0}$ M Jup and ${32.7}_{-3.2}^{+5.3}$ degrees. Despite only partial phase coverage for the c planet's orbit, we are able to constrain its mass and orbital parameters as well to ${6.9}_{-1.0}^{+1.7}$ M Jup and ${101}_{-33}^{+31}$ degrees. We find that coplanarity of the b and c orbits is strongly disfavored. Combined with the age of the system and the comparable masses of its planets, this suggests that planet-planet scattering may be responsible for the current configuration of the system.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- December 2021
- DOI:
- 10.3847/2041-8213/ac382c
- arXiv:
- arXiv:2111.06004
- Bibcode:
- 2021ApJ...922L..43B
- Keywords:
-
- 490;
- 492;
- 491;
- 489;
- 2130;
- 1332;
- 1827;
- Astrophysics - Earth and Planetary Astrophysics;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- doi:10.3847/2041-8213/ac382c