Projects per year
Abstract
The planetary system K2-24 is composed of two transiting low-density Neptunians locked in an almost perfect 2:1 resonance and showing large transit time variations (TTVs), and it is an excellent laboratory to search for signatures of planetary migration. Previous studies performed with K2, Spitzer, and RV data tentatively claimed a significant non-zero eccentricity for one or both planets, possibly high enough to challenge the scenario of pure disk migration through resonant capture. With 13 new CHEOPS light curves (seven of planet b, six of planet c), we carried out a global photometric and dynamical re-analysis by including all the available literature data as well. We obtained the most accurate set of planetary parameters to date for the K2-24 system, including radii and masses at 1% and 5% precision (now essentially limited by the uncertainty on stellar parameters) and non-zero eccentricities eb = 0.0498−0.0018+0.0011, ec = 0.0282−0.0007+0.0003 detected at very high significance for both planets. Such relatively large values imply the need for an additional physical mechanism of eccentricity excitation during or after the migration stage. Also, while the accuracy of the previous TTV model had drifted by up to 0.5 days at the current time, we constrained the orbital solution firmly enough to predict the forthcoming transits for the next ~15 years, thus enabling efficient follow-up with top-level facilities such as JWST or ESPRESSO.
| Original language | English |
|---|---|
| Article number | A349 |
| Number of pages | 16 |
| Journal | Astronomy & Astrophysics |
| Volume | 690 |
| Early online date | 22 Oct 2024 |
| DOIs | |
| Publication status | Published - Oct 2024 |
Keywords
- Techniques: photometric
- Techniques: spectroscopic
- Planets and satellites: detection
- Planets and satellites: dynamical evolution and stability
- Planets and satellites: gaseous planets
Fingerprint
Dive into the research topics of 'The K2-24 planetary system revisited by CHEOPS'. Together they form a unique fingerprint.-
REVEAL: REVEALing Signatures of Habitable Worlds Hidden by Stellar Activity
Cameron, A. (PI)
1/08/24 → 31/07/30
Project: Standard
-
AO2 - Professor Andrew Cameron: Project AO2 - Andrew Cameron
Cameron, A. (PI)
Science & Technology Facilities Council
1/04/21 → 31/03/24
Project: Standard
-
H2020 MSCA ITN EJD 2019: H2020 MSCA ITN EJD 2019 CHAMELEON
Helling, C. (PI)
Joint Research Centre European Commission
1/06/20 → 31/05/24
Project: Standard
Datasets
-
The K2-24 planetary system revisited by CHEOPS (dataset)
Wilson, T. G. (Creator) & Cameron, A. C. (Creator), Centre de Donnees Strasbourg (CDS), 2024
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/690/A349#/browse
Dataset
Cite this
- APA
- Author
- BIBTEX
- Harvard
- Standard
- RIS
- Vancouver