Updated Planetary Mass Constraints of the Young V1298 Tau System Using MAROON-X
Abstract
The early K-type T-Tauri star, V1298 Tau (V = 10 mag, age ≈ 20-30 Myr) hosts four transiting planets with radii ranging from 4.9 to 9.6 R ⊕. The three inner planets have orbital periods of ≈8-24 days while the outer planet's period is poorly constrained by single transits observed with K2 and the Transiting Exoplanet Survey Satellite (TESS). Planets b, c, and d are proto-sub-Neptunes that may be undergoing significant mass loss. Depending on the stellar activity and planet masses, they are expected to evolve into super-Earths/sub-Neptunes that bound the radius valley. Here we present results of a joint transit and radial velocity (RV) modeling analysis, which includes recently obtained TESS photometry and MAROON-X RV measurements. Assuming circular orbits, we obtain a low-significance (≈2σ) RV detection of planet c, implying a mass of ${19.8}_{-8.9}^{+9.3}\,{M}_{\oplus }$ and a conservative 2σ upper limit of <39 M ⊕. For planets b and d, we derive 2σ upper limits of M b < 159 M ⊕ and M d < 41 M ⊕, respectively. For planet e, plausible discrete periods of P e > 55.4 days are ruled out at the 3σ level while seven solutions with 43.3 < P e/d < 55.4 are consistent with the most probable 46.768131 ± 000076 days solution within 3σ. Adopting the most probable solution yields a 2.6σ RV detection with a mass of 0.66 ± 0.26 M Jup. Comparing the updated mass and radius constraints with planetary evolution and interior structure models shows that planets b, d, and e are consistent with predictions for young gas-rich planets and that planet c is consistent with having a water-rich core with a substantial (~5% by mass) H2 envelope.
- Publication:
-
The Astronomical Journal
- Pub Date:
- June 2023
- DOI:
- 10.3847/1538-3881/acc865
- arXiv:
- arXiv:2304.00797
- Bibcode:
- 2023AJ....165..250S
- Keywords:
-
- Exoplanet astronomy;
- Exoplanets;
- Mini Neptunes;
- Transits;
- Radial velocity;
- Exoplanet systems;
- 486;
- 498;
- 1063;
- 1711;
- 1332;
- 484;
- Astrophysics - Earth and Planetary Astrophysics
- E-Print:
- 18 pages, 13 figures, accepted for publication in AJ