The First Evidence of a Host Star Metallicity Cutoff in the Formation of Super-Earth Planets
Article
Boley, Kiersten M., Christiansen, Jessie L., Zink, Jon, Hardegree-Ullman, Kevin, Lee, Eve J., Hopkins, Philip F. H, Wang, Ji, Fernandes, Rachel B., Bergsten, Galen J. and Bhure, Sakhee. 2024. "The First Evidence of a Host Star Metallicity Cutoff in the Formation of Super-Earth Planets." The Astronomical Journal. 168 (3). https://doi.org/10.3847/1538-3881/ad6570
Article Title | The First Evidence of a Host Star Metallicity Cutoff in the Formation of Super-Earth Planets |
---|---|
ERA Journal ID | 1048 |
Article Category | Article |
Authors | Boley, Kiersten M., Christiansen, Jessie L., Zink, Jon, Hardegree-Ullman, Kevin, Lee, Eve J., Hopkins, Philip F. H, Wang, Ji, Fernandes, Rachel B., Bergsten, Galen J. and Bhure, Sakhee |
Journal Title | The Astronomical Journal |
Journal Citation | 168 (3) |
Article Number | 128 |
Number of Pages | 8 |
Year | 2024 |
Publisher | IOP Publishing |
Place of Publication | United States |
ISSN | 0004-6256 |
1538-3881 | |
Digital Object Identifier (DOI) | https://doi.org/10.3847/1538-3881/ad6570 |
Web Address (URL) | https://iopscience.iop.org/article/10.3847/1538-3881/ad6570 |
Abstract | Planet formation is expected to be severely limited in disks of low metallicity, owing to both the small solid mass reservoir and the low-opacity accelerating the disk gas dissipation. While previous studies have found a weak correlation between the occurrence rates of small planets (≲4R⊕) and stellar metallicity, so far no studies have probed below the metallicity limit beyond which planet formation is predicted to be suppressed. Here, we constructed a large catalog of ∼110,000 metal-poor stars observed by the TESS mission with spectroscopically derived metallicities, and systematically probed planet formation within the metal-poor regime ([Fe/H] ≤−0.5) for the first time. Extrapolating known higher-metallicity trends for small, short-period planets predicts the discovery of ∼68 super-Earths around these stars (∼85,000 stars) after accounting for survey completeness; however, we detect none. As a result, we have placed the most stringent upper limit on super-Earth occurrence rates around metal-poor stars (−0.75 < [Fe/H] ≤ −0.5) to date, ≤ 1.67%, a statistically significant (p-value = 0.000685) deviation from the prediction of metallicity trends derived with Kepler and K2. We find a clear host star metallicity cliff for super-Earths that could indicate the threshold below which planets are unable to grow beyond an Earth-mass at short orbital periods. This finding provides a crucial input to planet-formation theories, and has implications for the small planet inventory of the Galaxy and the galactic epoch at which the formation of small planets started. |
Keywords | Exoplanet astronomy |
Contains Sensitive Content | Does not contain sensitive content |
ANZSRC Field of Research 2020 | 5101. Astronomical sciences |
Byline Affiliations | Ohio State University, United States |
California Institute of Technology (Caltech), United States | |
NASA Exoplanet Science Institute, United States | |
University of Arizona, United States | |
McGill University, Canada | |
Pennsylvania State University, United States | |
Centre for Astrophysics |
Permalink -
https://research.usq.edu.au/item/z999v/the-first-evidence-of-a-host-star-metallicity-cutoff-in-the-formation-of-super-earth-planets
Download files
15
total views1
total downloads8
views this month1
downloads this month