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Title: 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 9.6R. 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 of19.88.9+9.3Mand a conservative 2σupper limit of <39M. For planets b and d, we derive 2σupper limits ofMb< 159MandMd< 41M, respectively. For planet e, plausible discrete periods ofPe> 55.4 days are ruled out at the 3σlevel while seven solutions with 43.3 <Pe/d< 55.4 are consistent with the most probable 46.768131 ± 000076 days solution within 3σ. Adopting the most probable solution yields a 2.6σRV detection with a mass of 0.66 ± 0.26MJup. 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) H2envelope.

 
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Award ID(s):
2108465
PAR ID:
10415592
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astronomical Journal
Volume:
165
Issue:
6
ISSN:
0004-6256
Format(s):
Medium: X Size: Article No. 250
Size(s):
Article No. 250
Sponsoring Org:
National Science Foundation
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