A calibration of the Rossby number from asteroseismology

Abstract

Stellar activity and rotation are tightly related in a dynamo process. Our understanding of this mechanism is mainly limited by our capability of inferring the properties of stellar turbulent convection. In particular, the convective turnover time is a key ingredient through the estimation of the stellar Rossby number, which is the ratio of the rotation period and the convective turnover time. In this work we propose a new calibration of the $(B-V)$ color index dependence of the convective turnover time, hence of the stellar Rossby number. Our new calibration is based on the stellar structure properties inferred through the detailed modeling of solar-like pulsators using asteroseismic observables. We show the impact of this calibration in a stellar activity -- Rossby number diagram by applying it to a sample of about 40,000 stars observed with Kepler and for which photometric activity proxy $S_{\mathrm{ph}}$ and surface rotation periods are available. Additionally, we provide a new calibration of the convective turnover time as function of the $(G_{\mathrm{BP}}-G_{\mathrm{RP}})$ color index for allowing applicability in the ESA Gaia photometric passbands.

5 pages, 2 figures, accepted for publication as a letter in A&A

References in corpus (18)

• The K2 Mission: Characterization and Early results
• ADIPLS -- the Aarhus adiabatic oscillation package
• Standing on the shoulders of Dwarfs: the Kepler asteroseismic LEGACY sample II - radii, masses, and ages
• ASTEC -- the Aarhus STellar Evolution Code
• Standing on the shoulders of Dwarfs: the $Kepler$ asteroseismic LEGACY sample I - oscillation mode parameters
• CoRoT reveals a magnetic activity cycle in a Sun-like star
• Asteroseismology of solar-type stars
• On differential rotation and overshooting in solar-like stars
• Impact on asteroseismic analyses of regular gaps in Kepler data
• DIAMONDS: a new Bayesian Nested Sampling tool. Application to Peak Bagging of solar-like oscillations
• Gap interpolation by inpainting methods : Application to Ground and Space-based Asteroseismic data
• Surface rotation of Kepler red giant stars
• High-precision abundances of elements in Kepler LEGACY stars. Verification of trends with stellar age
• Photospheric and chromospheric magnetic activity of seismic solar analogs. Observational inputs on the solar/stellar connection from Kepler and Hermes
• Revisiting the impact of stellar magnetic activity on the detectability of solar-like oscillations by Kepler
• Photospheric activity of the Sun with VIRGO and GOLF: Comparison with standard activity proxies
• Photometric variability as a proxy for magnetic activity and its dependence on metallicity
• ROOSTER: a machine-learning analysis tool for Kepler stellar rotation periods

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• Constraints on Magnetic Braking from the G8 Dwarf Stars 61 UMa and $\tau$ Cet
• Weakened Magnetic Braking in the Exoplanet Host Star 51 Peg
• Asteroseismology and Spectropolarimetry of the Exoplanet Host Star $\lambda$ Serpentis
• On the dynamics of overshooting convection in spherical shells: Effect of density stratification and rotation
• Statistics of BY Draconis Chromospheric Variable Stars
• On the origin of the dichotomy of stellar activity cycles
• Stochastic excitation of internal gravity waves in rotating late F-type stars: A 3D simulation approach
• Hunting for anti-solar differentially rotating stars using the Rossby number -- An application to the Kepler field
• Further evidence of the link between activity and metallicity using the flaring properties of stars in the Kepler field
• On the Evolution of Rotational Modulation Amplitude in Solar-mass Main-sequence Stars
• Signature of spin-down stalling in stellar magnetic activity. The case of the open cluster NGC 6811
• Estimating the Convective Turnover Time
• Photometric activity cycles in fast-rotating stars: Revisiting the reality of stellar activity cycle branches
• Testing the Rossby Paradigm: Weakened Magnetic Braking in early K-type Stars
• Searching for stellar cycles on low mass stars using TESS data
• Magnetic braking and dynamo evolution of $\beta$ Hydri
• Extending the Asteroseismic Calibration of the Stellar Rossby Number
• Surface activity of a Rossby sequence of cool Hyades stars
• Zeeman Doppler Imaging of $\tau$Ceti: The Weakest Magnetic Field Detected in a Sun-like Star