The Kepler Follow-up Observation Program. II. Stellar Parameters from Medium- and High-resolution Spectroscopy

Furlan, E.; Ciardi, D. R.; Cochran, W. D.; Everett, M. E.; Latham, D. W.; Marcy, G. W.; Buchhave, L. A.; Endl, M.; Isaacson, H.; Petigura, E. A.; Gautier, T. N., III; Huber, D.; Bieryla, A.; Borucki, W. J.; Brugamyer, E.; Caldwell, C.; Cochran, A.; Howard, A. W.; Howell, S. B.; Johnson, M. C.; MacQueen, P. J.; Quinn, S. N.; Robertson, P.; Mathur, S.; Batalha, N. M.
Bibliographical reference

The Astrophysical Journal, Volume 861, Issue 2, article id. 149, 22 pp. (2018).

Advertised on:
7
2018
Number of authors
25
IAC number of authors
1
Citations
31
Refereed citations
27
Description
We present results from spectroscopic follow-up observations of stars identified in the Kepler field and carried out by teams of the Kepler Follow-up Observation Program. Two samples of stars were observed over 6 yr (2009–2015): 614 standard stars (divided into “platinum” and “gold” categories) selected based on their asteroseismic detections and 2667 host stars of Kepler Objects of Interest (KOIs), most of them planet candidates. Four data analysis pipelines were used to derive stellar parameters for the observed stars. We compare the T eff, log(g), and [Fe/H] values derived for the same stars by different pipelines; from the average of the standard deviations of the differences in these parameter values, we derive error floors of ∼100 K, 0.2 dex, and 0.1 dex for T eff, log(g), and [Fe/H], respectively. Noticeable disagreements are seen mostly at the largest and smallest parameter values (e.g., in the giant star regime). Most of the log(g) values derived from spectra for the platinum stars agree on average within 0.025 dex (but with a spread of 0.1–0.2 dex) with the asteroseismic log(g) values. Compared to the Kepler Input Catalog (KIC), the spectroscopically derived stellar parameters agree within the uncertainties of the KIC but are more precise and thus an important contribution toward deriving more reliable planetary radii.
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Helio and Astero-Seismology and Exoplanets Search

The principal objectives of this project are: 1) to study the structure and dynamics of the solar interior, 2) to extend this study to other stars, 3) to search for extrasolar planets using photometric methods (primarily by transits of their host stars) and their characterization (using radial velocity information) and 4) the study of the planetary

Savita
Mathur