Characterizing Kepler Asteroseismic Targets

Abstract

Stellar structure and evolution can be studied in great detail by asteroseismic methods, provided data of high precision are available. We determine the effective temperature (Teff), surface gravity (log g), metallicity, and the projected rotational velocity (v sin i) of 44 Kepler asteroseismic targets using our high-resolution (R > 20,000) spectroscopic observations; these parameters will then be used to compute asteroseismic models of these stars and to interpret the Kepler light curves.We use the method of cross correlation to measure the radial velocity (RV) of our targets, while atmospheric parameters are derived using the ROTFIT code and spectral synthesis method. We discover three double-lined spectroscopic binaries, HIP 94924, HIP 95115, and HIP 97321 - for the last system, we provide the orbital solution, and we report two suspected single-lined spectroscopic binaries, HIP94112 and HIP 96062. For all stars from our sample we derive RV, v sin i, Teff, log g, and metallicity, and for six stars, we perform a detailed abundance analysis. A spectral classification is done for 33 targets. Finally, we show that the early-type star HIP 94472 is rotating slowly (v sin i = 13 kms/1) and we confirm its classification to the Am spectral type which makes it an interesting and promising target for asteroseismic modeling. The comparison of the results reported in this paper with the information in the Kepler Input Catalog (KIC) shows an urgent need for verification and refinement of the atmospheric parameters listed in the KIC. That refinement is crucial for making a full use of the data delivered by Kepler and can be achieved only by a detailed ground-based study.

The paper contains 6 figures and 7 tables. Table 1 will be published in full online only. Accepted for publication in Monthly Notices of the Royal Astronomical Society Main Journal

References in corpus (12)

• An absolutely calibrated effective temperature scale from the InfraRed Flux Method
• Kepler Asteroseismology Program: Introduction and First Results
• A new implementation of the infrared flux method using the 2MASS catalogue
• Improving Stellar and Planetary Parameters of Transiting Planet Systems: The Case of TrES-2
• Accurate fundamental parameters for Lower Main Sequence Stars
• Radius determination of solar-type stars using asteroseismology: What to expect from the Kepler mission
• Vertical distribution of Galactic disk stars IV - AMR and AVR from clump giants
• Asteroseismic Investigation of Known Planet Hosts in the Kepler Field
• The asteroseismic potential of Kepler: first results for solar-type stars
• The N2K Consortium. VII. Atmospheric Parameters of 1907 Metal-Rich Stars: Finding Planet-Search Targets
• Asteroseismology with the Kepler mission
• Asteroseismology of Solar-type stars with Kepler III. Ground-based Data

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• Planetary Candidates Observed by Kepler VI: Planet Sample from Q1-Q16 (47 Months)
• Verifying asteroseismically determined parameters of Kepler stars using hipparcos parallaxes: self-consistent stellar properties and distances
• LAMOST observations in the Kepler field. Database of low-resolution spectra
• Stroemgren survey for Asteroseismology and Galactic Archaeology: let the SAGA begin
• Results of a Search for gamma Dor and delta Sct Stars with the Kepler Spacecraft
• Rapid Rotation of Low-Mass Red Giants Using APOKASC: A Measure of Interaction Rates on the Post-main-sequence
• LAMOST observations in the Kepler field. II. Database of the low-resolution spectra from the five-year regular survey
• Asteroseismology of 1523 misclassified red giants using $\text{Kepler}$ data
• Detection of Solar-Like Oscillations, Observational Constraints, and Stellar Models for $\theta$ Cyg, the Brightest Star Observed by the {\it Kepler} Mission
• Physical properties of the eclipsing binary KIC 9851944 and analysis of its tidally-perturbed p- and g-mode pulsations