TOI-837 b has a true obliquity of 25.9+7.5-6.3 deg, the first planet younger than 100 Myr with accessible ψ incompatible with an aligned orbit, favoring primordial disc torque followed by disc-driven migration.
Planets and Stellar Activity: Hide and Seek in the CoRoT-7 system
4 Pith papers cite this work. Polarity classification is still indexing.
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Pith papers citing it
abstract
Since the discovery of the transiting super-Earth CoRoT-7b, several investigations have yielded different results for the number and masses of planets present in the system, mainly owing to the star's high level of activity. We re-observed CoRoT-7 in January 2012 with both HARPS and CoRoT, so that we now have the benefit of simultaneous radial-velocity and photometric data. This allows us to use the off-transit variations in the star's light curve to estimate the radial-velocity variations induced by the suppression of convective blueshift and the flux blocked by starspots. To account for activity-related effects in the radial-velocities which do not have a photometric signature, we also include an additional activity term in the radial-velocity model, which we treat as a Gaussian process with the same covariance properties (and hence the same frequency structure) as the light curve. Our model was incorporated into a Monte Carlo Markov Chain in order to make a precise determination of the orbits of CoRoT-7b and CoRoT-7c. We measure the masses of planets b and c to be 4.73 +/- 0.95 Mearth and 13.56 +/- 1.08 Mearth, respectively. The density of CoRoT-7b is (6.61 +/- 1.72)(Rp/1.58 Rearth)^(-3) g.cm^(-3), which is compatible with a rocky composition. We search for evidence of an additional planet d, identified by previous authors with a period close to 9 days. We are not able to confirm the existence of a planet with this orbital period, which is close to the second harmonic of the stellar rotation at around 7.9 days. Using Bayesian model selection we find that a model with two planets plus activity-induced variations is most favoured.
citation-role summary
method 1
citation-polarity summary
years
2026 4verdicts
UNVERDICTED 4roles
method 1polarities
use method 1representative citing papers
Introduces MGIC_rv, an information criterion that combines conditional RV likelihood with an effective parameter count for selecting multi-GP models focused on radial velocities.
Revised mass of 0.503 M_Earth and radius of 0.736 R_Earth for GJ 367 b give a density of 6.9 g cm^{-3} and an iron fraction of 50-70% via new tidal and composition modeling.
Three massive planets detected around HD125136 (2.26 MJup, 850 d) and HD127195 (0.66 and 0.78 MJup, 535 d and 834 d) via Bayesian Keplerian modeling of CORALIE RV series; one additional signal attributed to activity.
citing papers explorer
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A Model Selection Criterion for Multidimensional Gaussian Processes: Application to Radial Velocities
Introduces MGIC_rv, an information criterion that combines conditional RV likelihood with an effective parameter count for selecting multi-GP models focused on radial velocities.