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.
Three years of Sun-as-a-star radial-velocity observations on the approach to solar minimum
7 Pith papers cite this work. Polarity classification is still indexing.
7
Pith papers citing it
abstract
The time-variable velocity fields of solar-type stars limit the precision of radial-velocity determinations of their planets' masses, obstructing detection of Earth twins. Since 2015 July we have been monitoring disc-integrated sunlight in daytime using a purpose-built solar telescope and fibre feed to the HARPS-N stellar radial-velocity spectrometer. We present and analyse the solar radial-velocity measurements and cross-correlation function (CCF) parameters obtained in the first 3 years of observation, interpreting them in the context of spatially-resolved solar observations. We describe a Bayesian mixture-model approach to automated data-quality monitoring. We provide dynamical and daily differential-extinction corrections to place the radial velocities in the heliocentric reference frame, and the CCF shape parameters in the sidereal frame. We achieve a photon-noise limited radial-velocity precision better than 0.43 m s$^{-1}$ per 5-minute observation. The day-to-day precision is limited by zero-point calibration uncertainty with an RMS scatter of about 0.4 m s$^{-1}$. We find significant signals from granulation and solar activity. Within a day, granulation noise dominates, with an amplitude of about 0.4 m s$^{-1}$ and an autocorrelation half-life of 15 minutes. On longer timescales, activity dominates. Sunspot groups broaden the CCF as they cross the solar disc. Facular regions temporarily reduce the intrinsic asymmetry of the CCF. The radial-velocity increase that accompanies an active-region passage has a typical amplitude of 5 m s$^{-1}$ and is correlated with the line asymmetry, but leads it by 3 days. Spectral line-shape variability thus shows promise as a proxy for recovering the true radial velocity.
years
2026 7representative 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.
3D MHD simulations of solar faculae reveal a center-to-limb transition in induced radial velocity from redshift to blueshift at heliocentric angles above 60 degrees, producing a phase-lagged transit profile and spectral-line dependence.
SRA-derived photospheric activity indicators track stellar RV variability up to a factor of two better than classical proxies like logR'HK across 14 G/K stars.
TOI-1533 is confirmed as a rare compact system hosting an inner sub-Neptune and an outer hot super-Neptune-mass giant with nearly equal masses and very different radii.
New instrument suite for ultra-high resolution solar spectroscopy with laser frequency comb calibration enabling precise Sun-as-a-star and spatially resolved line studies.
Three Jupiter-mass planets are detected around two low-luminosity red giants with 15–18 yr CORALIE RVs; a multi-exposure strategy averages pulsations below 5 m/s.
citing papers explorer
-
The 35-Myr old infant planet TOI-837 b has a mildly misaligned orbit
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.
-
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.
-
Decoding the Radial Velocity Signatures of Solar Faculae with 3D MHD Simulations
3D MHD simulations of solar faculae reveal a center-to-limb transition in induced radial velocity from redshift to blueshift at heliocentric angles above 60 degrees, producing a phase-lagged transit profile and spectral-line dependence.
-
Spectral Ratio Analysis: probing of a new suite of stellar activity indicators as a tool for astrophysical noise mitigation
SRA-derived photospheric activity indicators track stellar RV variability up to a factor of two better than classical proxies like logR'HK across 14 G/K stars.
-
The GAPS programme at TNG: LXXVI. TOI-1533: a compact system hosting a super-Neptune-mass pair with disparate radii
TOI-1533 is confirmed as a rare compact system hosting an inner sub-Neptune and an outer hot super-Neptune-mass giant with nearly equal masses and very different radii.
-
Observing the integrated and spatially resolved Sun with ultra-high spectral resolution
New instrument suite for ultra-high resolution solar spectroscopy with laser frequency comb calibration enabling precise Sun-as-a-star and spatially resolved line studies.
-
CORALIE radial-velocity search for companions around evolved stars (CASCADES) V. Three planetary companions and achievable precision
Three Jupiter-mass planets are detected around two low-luminosity red giants with 15–18 yr CORALIE RVs; a multi-exposure strategy averages pulsations below 5 m/s.