Multicolour Validation of Two Temperate Mini-Neptunes Around M-dwarf Habitable Zones
Fuente:
arXiv
Gespeichert in:
| Hauptverfasser: | , , , , , , , , , , , , , , , , , , , |
|---|---|
| Format: | Preprint |
| Veröffentlicht: |
2025
|
| Schlagworte: | |
| Online-Zugang: | |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| _version_ | 1866914401455439872 |
|---|---|
| author | Jiang, Chengzi Selezneva, Aleksandra Parviainen, Hannu Murgas, Felipe Pallé, Enric Fernández-Rodríguez, Gareb Geraldía-González, Samuel Orell-Miquel, Jaume Narita, Norio Fukui, Akihiko de Leon, Jerome Fukuda, Izuru Ikuta, Kai Kawauchi, Kiyoe Howell, Steve B. Littlefield, Colin Deveny, Sarah J. Twicken, Joseph D. Schwarz, Richard P. Shporer, Avi |
| author_facet | Jiang, Chengzi Selezneva, Aleksandra Parviainen, Hannu Murgas, Felipe Pallé, Enric Fernández-Rodríguez, Gareb Geraldía-González, Samuel Orell-Miquel, Jaume Narita, Norio Fukui, Akihiko de Leon, Jerome Fukuda, Izuru Ikuta, Kai Kawauchi, Kiyoe Howell, Steve B. Littlefield, Colin Deveny, Sarah J. Twicken, Joseph D. Schwarz, Richard P. Shporer, Avi |
| contents | For small planets orbiting within the habitable zones of their host stars, multicolour validation via photometric transit observations offers an efficient alternative to prioritize targets before intensive radial-velocity follow-up, thereby expanding the sample of habitable-zone exoplanets amenable for atmospheric characterisation. In this study, we validate two exceptional habitable-zone TESS candidates, orbiting around M-dwarfs, as genuine planets, precisely determining their transit and physical parameters. We perform Bayesian model comparison by jointly fitting multicolour light curves from TESS and ground-based follow-up, including observations with HiPERCAM at the 10.4-m GTC. Our approach uses wavelength-dependent transit depth variations and precise transit geometry to reject false positives. We validate TOI-2094 b and TOI-7166 b as two new benchmark temperate mini-Neptunes. TOI-2094 b (1.90 $R_{\oplus}$) orbits its M3V star with a period of $\sim$18.79 days, well within the habitable zone ($\sim$0.98 Earth insolation). TOI-7166 b (2.39 $R_{\oplus}$) orbits its M4.5V host star with a period of $\sim$12.92 days, placing it near the inner edge of the habitable zone ($\sim$1.93 Earth insolation). Statistical mass and density estimates suggest that TOI-2094 b may be a volatile-rich planet, such as a water world or a gaseous planet, and is less likely to be rocky, while TOI-7166 b is likely to be volatile-rich. Both planets are of great interest for detailed atmospheric characterisation with the JWST and future ELTs, which requires further precise mass measurements. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2512_06817 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Multicolour Validation of Two Temperate Mini-Neptunes Around M-dwarf Habitable Zones Jiang, Chengzi Selezneva, Aleksandra Parviainen, Hannu Murgas, Felipe Pallé, Enric Fernández-Rodríguez, Gareb Geraldía-González, Samuel Orell-Miquel, Jaume Narita, Norio Fukui, Akihiko de Leon, Jerome Fukuda, Izuru Ikuta, Kai Kawauchi, Kiyoe Howell, Steve B. Littlefield, Colin Deveny, Sarah J. Twicken, Joseph D. Schwarz, Richard P. Shporer, Avi Earth and Planetary Astrophysics For small planets orbiting within the habitable zones of their host stars, multicolour validation via photometric transit observations offers an efficient alternative to prioritize targets before intensive radial-velocity follow-up, thereby expanding the sample of habitable-zone exoplanets amenable for atmospheric characterisation. In this study, we validate two exceptional habitable-zone TESS candidates, orbiting around M-dwarfs, as genuine planets, precisely determining their transit and physical parameters. We perform Bayesian model comparison by jointly fitting multicolour light curves from TESS and ground-based follow-up, including observations with HiPERCAM at the 10.4-m GTC. Our approach uses wavelength-dependent transit depth variations and precise transit geometry to reject false positives. We validate TOI-2094 b and TOI-7166 b as two new benchmark temperate mini-Neptunes. TOI-2094 b (1.90 $R_{\oplus}$) orbits its M3V star with a period of $\sim$18.79 days, well within the habitable zone ($\sim$0.98 Earth insolation). TOI-7166 b (2.39 $R_{\oplus}$) orbits its M4.5V host star with a period of $\sim$12.92 days, placing it near the inner edge of the habitable zone ($\sim$1.93 Earth insolation). Statistical mass and density estimates suggest that TOI-2094 b may be a volatile-rich planet, such as a water world or a gaseous planet, and is less likely to be rocky, while TOI-7166 b is likely to be volatile-rich. Both planets are of great interest for detailed atmospheric characterisation with the JWST and future ELTs, which requires further precise mass measurements. |
| title | Multicolour Validation of Two Temperate Mini-Neptunes Around M-dwarf Habitable Zones |
| topic | Earth and Planetary Astrophysics |
| url | https://arxiv.org/abs/2512.06817 |