Abstract
We present the discovery of two exoplanets transiting TOI-836 (TIC 440887364) using data from TESS Sector 11 and Sector 38. TOI-836 is a bright (T = 8.5 mag), high proper motion (∼200 mas yr−1), low metallicity ([Fe/H]≈−0.28) K-dwarf with a mass of 0.68 ± 0.05 M and a radius of 0.67 ± 0.01 R. We obtain photometric follow-up observations with a variety of facilities, and we use these data sets to determine that the inner planet, TOI-836 b, is a 1.70 ± 0.07 R super-Earth in a 3.82-d orbit, placing it directly within the so-called ‘radius valley’. The outer planet, TOI-836 c, is a 2.59 ± 0.09 R mini-Neptune in an 8.60-d orbit. Radial velocity measurements reveal that TOI-836 b has a mass of 4.5 ± 0.9 M, while TOI-836 c has a mass of 9.6 ± 2.6 M. Photometric observations show Transit Timing Variations (TTVs) on the order of 20 min for TOI-836 c, although there are no detectable TTVs for TOI-836 b. The TTVs of planet TOI-836 c may be caused by an undetected exterior planet. © 2023 Oxford University Press. All rights reserved.
| Original language | English |
|---|---|
| Pages (from-to) | 3649-3668 |
| Number of pages | 20 |
| Journal | Monthly Notices of the Royal Astronomical Society |
| Volume | 520 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 2023 |
Subject classification (UKÄ)
- Astronomy, Astrophysics and Cosmology
Free keywords
- planets and satellites: detection
- stars: individual: TOI-836 (TIC 440887364, GAIA EDR3 6230733559097425152)
- techniques: photometric
- techniques: radial velocities
- Earth (planet)
- Photometry
- Planets
- Satellites
- Exo-planets
- Neptune
- Photometrics
- Planets and satellites: detections
- Star: individual: TOI-836 (TIC 440887364, GAIA EDR3 6230733559097425152)
- Stars: individual: proxima Centauri
- Techniques: photometric
- Techniques: radial velocities
- Timing variations
- Transit timing
- Orbits