Stellar Atmospheres of Nearby Young Solar Analogs

Abstract

High-resolution (R ~ 90,000) spectra of 34 nearby, young Sun-like stars were analyzed using stellar atmosphere models to estimate effective photosphere temperatures, surface gravities, and the abundance of certain heavy elements (C, Na, Mg, Si, S, Ca, Ti, Fe, and Ni). The effective temperatures derived from spectroscopy were compared with temperatures estimated using optical and near-infrared photometry. In many cases the spectroscopic temperatures are significantly higher than the photometric estimates, possibly as a result of spottedness or chromospheric activity on these active stars. Values of effective temperature, surface gravity, and luminosity were compared to theoretical stellar evolution tracks and the evolutionary status of these objects was evaluated. The correlation between heavy element abundance patterns and kinematics (space motion) was also examined. Two nearby stars that were tentatively assigned to the Hyades cluster based on kinematics have Fe abundances that are also consistent with membership in that cluster. Members of the Ursa Major kinematic group exhibit a range of [Fe/H] values but have monotonic [Si/Fe]. These two observations suggest that heterogeneous incorporation of the heavy elements into protostars is creating the variation in metallicity. Local Association members have a distinctly different Si/Fe that probably reflects their distinct origin and chemical inheritance.

to appear in New Astronomy; gzipped tar file containing AASTeX file and 13 enscapsulated PS figures

References in corpus (2)

• The metal-rich nature of stars with planets
• The CORALIE survey for southern extrasolar planets V: 3 new extrasolar planets

Cited by in corpus (23)

• Evolution of the Solar Activity over Time and Effects on Planetary Atmospheres: I. High-energy Irradiances (1-1700 A)
• Statistical properties of exoplanets II. Metallicity, orbital parameters, and space velocities
• Frequency of Debris Disks around Solar-Type Stars: First Results from a Spitzer/MIPS Survey
• Coronal Evolution of the Sun in Time: High-Resolution X-Ray Spectroscopy of Solar Analogs with Different Ages
• Bayesian Ages for Early-Type Stars from Isochrones Including Rotation, and a Possible Old Age for the Hyades
• Abundance Analysis of Planetary Host Stars I. Differential Iron Abundances
• Evolution of the solar activity over time and effects on planetary atmospheres. II. kappa^1 Ceti, an analog of the Sun when life arose on Earth
• Far-Ultraviolet Activity Levels of F, G, K, and M dwarf Exoplanet Host Stars
• Activity and the Li abundances in the FGK dwarfs
• On the common origin of the AB Dor moving group and the Pleiades cluster
• Reaching the boundary between stellar kinematic groups and very wide binaries. II. alpha Lib + KU Lib: a common proper motion system in Castor separated by 1.0 pc
• Radio emission and mass loss rate limits of four young solar-type stars
• A substellar component orbiting the F-star 30 Ari B
• Spectroscopic properties of cool Ursa Major group members
• Spectroscopic abundance analysis of dwarfs in young open cluster IC 4665
• Photospheric and chromospheric activity in four young solar-type stars
• Reconstructing the XUV Spectra of Active Sun-like Stars Using Solar Scaling Relations with Magnetic Flux
• Hot Grain Dynamics by Electric Charging and Magnetic Trapping in Debris Disks
• The uvbyHbeta Metallicity Calibration for G and K Dwarfs
• The Fundamental Stellar Parameters of FGK Stars in the SEEDS Survey
• Spectral synthesis analysis and radial velocity study of the northern F-, G-, and K-type flare-stars
• Correlating Intrinsic Stellar Parameters with Mg II Self-Reversal Depths
• Periodicity in some light curves of the solar analogue V352 CMa