In:
Astronomy & Astrophysics, EDP Sciences, Vol. 677 ( 2023-9), p. A38-
Abstract:
We present the discovery and validation of two TESS exoplanets orbiting nearby M dwarfs: TOI-2084 b, and TOI-4184b. We characterized the host stars by combining spectra from Shane /Kast and Magellan /FIRE, spectral energy distribution analysis, and stellar evolutionary models. In addition, we used Gemini-South/Zorro & -North/Alopeke high-resolution imaging, archival science images, and statistical validation packages to support the planetary interpretation. We performed a global analysis of multi-colour photometric data from TESS and ground-based facilities in order to derive the stellar and planetary physical parameters for each system. We find that TOI-2084 band TOI-4184 bare sub-Neptune-sized planets with radii of R p = 2.47 ± 0.13 R ⊕ and R p = 2.43 ± 0.21 R ⊕ , respectively. TOI-2084 b completes an orbit around its host star every 6.08 days, has an equilibrium temperature of T eq = 527 ± 8 K and an irradiation of S p = 12.8 ± 0.8 S ⊕ . Its host star is a dwarf of spectral M2.0 ± 0.5 at a distance of 114 pc with an effective temperature of T eff = 3550 ± 50 K, and has a wide, co-moving M8 companion at a projected separation of 1400 au. TOI-4184 b orbits around an M5.0 ± 0.5 type dwarf star ( K mag = 11.87) each 4.9 days, and has an equilibrium temperature of T eq = 412 ± 8 K and an irradiation of S p = 4.8 ± 0.4 S ⊕ . TOI-4184 is a metal poor star ([Fe/H] = −0.27 ± 0.09 dex) at a distance of 69 pc with an effective temperature of T eff = 3225 ± 75 K. Both planets are located at the edge of the sub-Jovian desert in the radius-period plane. The combination of the small size and the large infrared brightness of their host stars make these new planets promising targets for future atmospheric exploration with JWST.
Type of Medium:
Online Resource
ISSN:
0004-6361
,
1432-0746
DOI:
10.1051/0004-6361/202346838
Language:
English
Publisher:
EDP Sciences
Publication Date:
2023
detail.hit.zdb_id:
1458466-9
SSG:
16,12
