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.
The Changing Face of $\alpha$ Centauri B: Probing plage and stellar activity in K-dwarfs
3 Pith papers cite this work. Polarity classification is still indexing.
3
Pith papers citing it
abstract
A detailed knowledge of stellar activity is crucial for understanding stellar dynamos, as well as pushing exoplanet radial-velocity detection limits towards Earth analogue confirmation. We directly compare archival HARPS spectra taken at the minimum in $\alpha$ Cen B's activity cycle to a high-activity state when clear rotational modulation of $\log{R'_{HK}}$ is visible. Relative to the inactive spectra, we find a large number of narrow pseudo-emission features in the active spectra with strengths that are rotationally modulated. These features most likely originate from plage, spots, or a combination of both. They also display radial velocity variations of $\sim$300 m s$^{-1}$ - consistent with an active region rotating across the stellar surface. Furthermore, we see evidence that some of the lines originating from the `active immaculate' photosphere appear broader relative to the `inactive immaculate' case. This may be due to enhanced contributions of e.g. magnetic bright points to these lines, which then causes additional line broadening. More detailed analysis may enable measurements of plage and spot coverage using single spectra in the future.
years
2026 3representative citing papers
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.
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.
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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.
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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.