A New Age-Activity Relation For Solar Analogs that Accounts for Metallicity

Abstract

Determining stellar ages is challenging, particularly for cooler main-sequence stars. Magnetic evolution offers an observational alternative for age estimation via the age-chromospheric activity (AC) relation. We evaluate the impact of metallicity on this relation using near one-solar-mass stars across a wide metallicity range. We analyze a sample of 358 solar-type stars with precise spectroscopic parameters determined through a line-by-line differential technique and with ages derived using Yonsei-Yale isochrones. We measured chromospheric activity (S-index) using high-quality HARPS spectra, calibrated to the Mount Wilson system, and converted to the $R_{\mathrm{H}K}^{\prime }(T_{\mathrm{eff}})$ index with a temperature-based photospheric correction. Our findings show that the AC relation for $R_{\mathrm{H}K}^{\prime }(T_{\mathrm{eff}})$ is strongly influenced by metallicity. We propose a new age-activity-metallicity relation for solar-type main-sequence (MS) stars ($\log g\gtrsim 4.2$) with temperatures 5370 $\lesssim$ $T_{\mathrm{eff}}$ $\lesssim$ 6530 K and metallicities from -0.7 to +0.3 dex. We show that taking metallicity into account significantly enhances chromospheric ages' reliability, reducing the residuals' root mean square (RMS) relative to isochronal ages from 2.6 Gyr to 0.92 Gyr. This reflects a considerable improvement in the errors of chromospheric ages, from 53\% to 15\%. The precision level achieved in this work is also consistent with previous age-activity calibration from our group using solar twins.

10 pages, 4 figures

References in corpus (38)

• Array Programming with NumPy
• Astropy: A Community Python Package for Astronomy
• The Gaia mission
• The Astropy Project: Sustaining and Growing a Community-oriented Open-source Project and the Latest Major Release (v5.0) of the Core Package
• Gaia Data Release 3: Summary of the content and survey properties
• Binary companions of evolved stars in APOGEE DR14: Search method and catalog of ~5,000 companions
• The SIMBAD astronomical database
• Gaia Data Release 2: The astrometric solution
• Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics
• Towards Better Age Estimates for Stellar Populations: The Y^2 Isochrones for Solar Mixture
• astroquery: An Astronomical Web-Querying Package in Python
• Chromospheric CaII Emission in Nearby F, G, K, and M stars
• Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 parsecs: The Southern Sample
• The YY Isochrones for alpha-element Enhanced Mixtures
• High-precision abundances of elements in solar twin stars: Trends with stellar age and elemental condensation temperature
• Age determination for 269 $Gaia$ DR2 Open Clusters
• The Solar Twin Planet Search. I. Fundamental parameters of the stellar sample
• The remarkable solar twin HIP 56948: a prime target in the quest for other Earths
• Chromospheric activity as age indicator
• The influence of atomic diffusion on stellar ages and chemical tagging
• Stellar chromospheric activity of 1,674 FGK stars from the AMBRE-HARPS sample I. A catalogue of homogeneous chromospheric activity
• Chromospheric Activities and Kinematics for Solar Type Dwarfs and Subgiants: Analysis of the Activity Distribution and the AVR
• The Solar Twin Planet Search: The age - chromospheric activity relation
• Stellar Chemical Abundances: In Pursuit of the Highest Achievable Precision
• 18 Sco: a solar twin rich in refractory and neutron-capture elements. Implications for chemical tagging
• The temporal evolution of neutron-capture elements in the Galactic discs
• The nucleosynthetic history of elements in the Galactic disk: [X/Fe] - age relations from high-precision spectroscopy
• An Activity Catalogue of Southern Stars
• High Precision Abundances of the Old Solar Twin HIP 102152: Insights on Li Depletion from the Oldest Sun
• Metallicity effects on the chromospheric activity-age relation for late-type dwarfs
• ACTIN: A tool to calculate stellar activity indices
• The age-mass-metallicity-activity relation for solar-type stars: Comparisons with asteroseismology and the NGC 188 open cluster
• Detailed chemical compositions of planet hosting stars: I. Exploration of possible planet signatures
• Fine structure of the chromospheric activity in Solar-type stars - The Halpha Line
• Metallicity and age effects on lithium depletion in solar analogues
• Lithium depletion in solar analogs: age and mass effects
• The [Y/Mg] chemical clock in the Galactic Disk: The influence of metallicity and Galactic population in the solar neighbourhood
• Fine Structure of the Age-Chromospheric Activity Relation in Solar-Type Stars: II. H$\alpha$ Line

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