Exploration Gear & Tech

The TESS-Keck Survey XXIV: Outer Giants May be More Prevalent in the Presence of Inner Small Planets

By Keith Cowing
Status Report
astro-ph.EP
January 14, 2025
Filed under , , , , , , ,
The TESS-Keck Survey XXIV: Outer Giants May be More Prevalent in the Presence of Inner Small Planets
Close-in small planets and their distant giant companions. Masses and periods of exoplanets from our survey (bold squares) and the NASA Exoplanet Archive (faded circles) for context . Red/blue points indicate planets discovered using the transit/RV method. Red squares show true masses of transiting planets in the Distant Giants Survey measured by RVs (Polanski et al. 2024), while blue squares show minimum mass measurements (M sin i). For systems with multiple transiting planets, we show the parameters of the transiting planet with the lowest TOI designation that passed our filters. Red squares with yellow borders indicate systems in which we detected a linear/quadratic trend. Giant planets in our sample are connected to the inner planet in their system by a black line. The box corresponds to our nominal definition of a Distant Giant. — astro-ph.EP

We present the results of the Distant Giants Survey, a three-year radial velocity (RV) campaign to search for wide-separation giant planets orbiting Sun-like stars known to host an inner transiting planet.

We defined a distant giant to have a = 1–10 AU and Mpsini=70−4000 mearth~ = 0.2-12.5mj, and required transiting planets to have a <1 AU and Rp=1−4rearth. We assembled our sample of 47 stars using a single selection function, and observed each star at monthly intervals to obtain ≈30 RV observations per target.

The final catalog includes a total of twelve distant companions: four giant planets detected during our survey, two previously known giant planets, and six objects of uncertain disposition identified through RV/astrometric accelerations. Statistically, half of the uncertain objects are planets and the remainder are stars/brown dwarfs. We calculated target-by-target completeness maps to account for missed planets.

We found evidence for a moderate enhancement of distant giants (DG) in the presence of close-in small planets (CS), P(DG|CS) = 30+14−12%, over the field rate of P(DG) = 16+2−2%. No enhancement is disfavored (p∼ 8%). In contrast to a previous study, we found no evidence that stellar metallicity enhances P(DG|CS).

We found evidence that distant giant companions are preferentially found in systems with multiple transiting planets and have lower eccentricities than randomly selected giant planets. This points toward dynamically cool formation pathways for the giants that do not disturb the inner systems.

Judah Van Zandt, Erik A. Petigura, Jack Lubin, Lauren M. Weiss, Emma V. Turtelboom, Tara Fetherolf, Joseph M. Akana Murphy, Ian J. M. Crossfield, Greg Gilbert, Teo Mocnik, Natalie M. Batalha, Courtney Dressing, Benjamin Fulton, Andrew W. Howard, Daniel Huber, Howard Isaacson, Stephen R. Kane, Paul Robertson, Arpita Roy, Isabel Angelo, Aida Behmard, Corey Beard, Ashley Chontos, Fei Dai, Paul A. Dalba, Steven Giacalone, Michelle L. Hill, Lea A. Hirsch, Rae Holcomb, Steve B. Howell, Andrew W. Mayo, Mason G. MacDougall, Daria Pidhorodetska, Alex S. Polanski, James Rogers, Lee J. Rosenthal, Ryan A. Rubenzahl, Nicholas Scarsdale, Dakotah Tyler, Samuel W. Yee, Jon Zink

Comments: 32 pages, 20 figures, 4 tables. Comments welcome
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2501.06342 [astro-ph.EP] (or arXiv:2501.06342v1 [astro-ph.EP] for this version)
https://doi.org/10.48550/arXiv.2501.06342
Focus to learn more
Submission history
From: Judah Van Zandt
[v1] Fri, 10 Jan 2025 20:51:58 UTC (11,038 KB)
https://arxiv.org/abs/2501.06342
Astrobiology,

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻