| Title: |
Mass estimates of the young TOI-451 transiting planets: multidimensional Gaussian Process on stellar spectroscopic and photometric signals |
| Authors: |
Barragán, O; Mallorquín, M; Fernández-Fernández, J; Hawthorn, F; Freckelton, AV; Lafarga, M; Cretignier, M; Eschen, YNE; Gill, S; Béjar, VJS; Lodieu, N; Yu, H; Wilson, TG; Anderson, D; Apergis, I; Battley, M; Bryant, EM; Cortés-Zuleta, P; Gillen, E; Jenkins, JS; Klein, B; McCormac, J; Meech, A; Meier-Valdés, E; Aigrain, S |
| Publisher Information: |
Oxford University Press |
| Publication Year: |
2026 |
| Collection: |
Oxford University Research Archive (ORA) |
| Description: |
The young TOI-451 planetary system, aged 125 Myr, provides a unique opportunity to test theories of planetary internal structures and atmospheric mass-loss through examination of its three transiting planets. We present an exhaustive photometric and spectroscopic follow-up to determine the orbital and physical properties of the system. We perform multidimensional Gaussian Process regression with the code pyaneti on spectroscopic time-series and NGTS/LCO light curves to disentangle the stellar and planetary signal in ESPRESSO radial velocities. We show how contemporaneous photometry serves as an activity indicator to inform RV modelling within a multidimensional Gaussian Processes framework. We argue that this can be exploited when spectroscopic observations are adversely affected by low signal-to-noise and/or poor sampling. We estimate the Doppler semi-amplitudes of , , and . This translates in 2 mass estimates for TOI-451 b and d of and ; as well as a mass upper limit for TOI-451 c of . The derived planetary properties suggest that planets c and d contain significant hydrogen-rich envelopes. The inferred parameters of TOI-451 b are consistent with either a rocky world that still retains a small hydrogen envelope or a water world. These insights make the TOI-451 system an ideal laboratory for future follow-up studies aimed at measuring atmospheric compositions, detecting atmospheric mass-loss signatures, and further exploring planetary formation and evolution processes. |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| Relation: |
https://doi.org/10.1093/mnras/stag087 |
| DOI: |
10.1093/mnras/stag087 |
| Availability: |
https://doi.org/10.1093/mnras/stag087; https://ora.ox.ac.uk/objects/uuid:1800785d-e0d1-47a4-8a89-5e05bca3356e |
| Rights: |
info:eu-repo/semantics/openAccess ; CC Attribution (CC BY) |
| Accession Number: |
edsbas.1AE60D03 |
| Database: |
BASE |