Exoplanets in ancient stellar populations: occurrence constraints and hot-Jupiter candidates in the Galactic halo
Clicks: 9
ID: 322571
2026
Article Quality & Performance Metrics
Overall Quality
Not rated
Combines reader engagement with the AI quality analysis. This
article has not been analysed, so there is no overall score —
reader engagement is measured and shown alongside.
Reader Engagement
Emerging Content
0.3
/100
9 views
1 readers
AI Quality Assessment
Not analyzed
Readership in this journal
EmergingRanked #36 of 892 articles by views in monthly notices of the royal astronomical society
Most read
Least read
Bar heights use a square-root scale. Only the 120 most-read articles are drawn; the journal has 892 in total.
Mint this article as an NFT
Not yet mintedCreate a permanent, verifiable on-chain record of this article on the Scimatic Network. The NFT is held in your Journament account, and you can withdraw it to your own wallet at any time.
5
SUSD
one-off · no wallet required
Abstract
Abstract The Galactic halo preserves a record of the Milky Way’s earliest assembly and contains both in-situ stars and stars accreted from dwarf galaxies. Possible planets around these stars, therefore, probe formation in ancient, metal-poor environments, including systems of extragalactic origin. We present a search for short-period transiting planets around kinematically selected halo dwarfs using Gaia DR3 and TESS, focusing on planets with periods of 1 < P < 10 days. We identify two hot-Jupiter (HJ) candidates, one in the in-situ and one in the accreted halo, although the latter is highly grazing and excluded from the occurrence analysis. The accreted halo planet candidate, if confirmed, would orbit the most metal-poor HJ host known ([Fe/H] ≈−1). Using injection–recovery tests and automated vetting, we constrain occurrence in the full halo, in-situ, and accreted samples. In the HJ regime (8 R⊕ < Rp < 22 R⊕, 1 day < P < 10 days), the non-grazing candidate implies an overall halo occurrence rate of $0.13^{+0.12}_{-0.07}\%$ if planetary, while the absence of confirmed detections gives a corresponding 1σ upper limit of <0.14%. For the in-situ halo, we infer $0.17^{+0.17}_{-0.10}\%$ (or <0.19% assuming no detections), while for the accreted halo we derive an upper limit of <0.56%. These rates lie well below the corresponding short-period giant-planet occurrence measured in the Galactic disc. A forward model assuming Kepler-like occurrence also predicts 10 ± 3 detections compared with at most one observed. We find no significant occurrence difference between the in-situ and accreted halo populations, strengthening the evidence that close-in giant planets are rare across the old, metal-poor halo.
| Reference Key |
openalex_W7170215694
Use this key to autocite in the manuscript while using
SciMatic Manuscript Manager or Thesis Manager
|
|---|---|
| Authors | Dolev Bashi, Michelle Kunimoto, Kevin K. Hardegree-Ullman, Tianjun Gan, Sharon X. Wang, Zhen Yuan |
| Journal | monthly notices of the royal astronomical society |
| Year | 2026 |
| DOI |
10.1093/mnras/stag1386
|
| URL | |
| Keywords | Keywords not found |
Citations
No citations found. To add a citation, contact the admin at info@scimatic.org
Comments
No comments yet. Be the first to comment on this article.