Spectral Properties of Cool Stars: Extended Abundance Analysis of 1,617 Planet-search Stars
Year: 2016
Type: article
Abstract: ABSTRACT We present a catalog of uniformly determined stellar properties and abundances for 1,617 F, G, and K stars using an automated spectral synthesis modeling procedure. All stars were observed using the HIRES spectrograph at Keck Observatory. Our procedure used a single line list to fit model spectra to observations of all stars to determine effective temperature, surface gravity, metallicity, projected rotational velocity, and the abundances of 15 elements (C, N, O, Na, Mg, Al, Si, Ca, Ti, V, Cr, Mn, Fe, Ni, and Y). Sixty percent of the sample had Hipparcos parallaxes and V-band photometry, which we combined with the spectroscopic results to obtain mass, radius, and luminosity. Additionally, we used the luminosity, effective temperature, metallicity and α-element enhancement to interpolate in the Yonsei–Yale isochrones to derive mass, radius, gravity, and age ranges for those stars. Finally, we determined new relations between effective temperature and macroturbulence for dwarfs and subgiants. Our analysis achieved precisions of 25 K in , 0.01 dex in [M/H], 0.028 dex for , and 0.5 km s−1 in based on multiple observations of the same stars. The abundance results were similarly precise, between ∼0.01 and ∼0.04 dex, though trends with respect to remained for which we derived empirical corrections. The trends, though small, were much larger than our uncertainties and are shared with published abundances. We show that changing our model atmosphere grid accounts for most of the trend in [M/H] between 5000 and 5500 K, indicating a possible problem with the atmosphere models or opacities.
Authors: John M. Brewer, Debra A. Fischer, Jeff A. Valenti, Nikolai Piskunov
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Awards: PLANET HUNTERS (PH) IS A WELL-ESTABLISHED AND SUCCESSFUL WEB INTERFACE THAT ALLOWS CITIZEN SCIENTISTS TO SEARCH FOR TRANSITING PLANETS IN THE NASA KE, THE ROCKY PLANET SURVEYIN DIRECT SUPPORT OF THE NASA ORIGINS PROGRAM, WE PROPOSE THE ROCKY PLANET SURVEY, A HIGH CADENCE EXOPLANET SEARCH OF SIXTY L
OpenAlex ID: W2468696237