2013/11/30 by Subo Dong, Zheng Zheng, Zhaohuan Zhu +8 · 2 citations
Physics and Astronomy · #Astro and Planetary Science #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #LAMOST #Metallicity #Physics #Sky #Spectral line #Stars #Stellar, planetary, and galactic studies #Telescope #astro-ph.EP #astro-ph.SR
paper · pdf · doi:10.1088/2041-8205/789/1/l3
published as 2014, ApJL, 789, L3
openalex publication_date 2014/06/11 · arxiv created 2014/06/12 · arxiv updated 2014/06/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We use 12,000 stars from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) spectroscopic survey data to show that the metallicities of Kepler field stars as given in the Kepler Input Catalog (KIC) systematically underestimate both the true metallicity and the dynamic range of the Kepler sample. Specifically, to the first order approximation, we find [Fe/H] KIC = −0.20 + 0.43[Fe/H] LAMOST , with a scatter of ∼0.25 dex, due almost entirely to errors in KIC. This relation is most secure for −0.3 < [Fe/H] LAMOST < +0.4 where we have >200 comparison stars per 0.1 dex bin and good consistency is shown between metallicities determined by LAMOST and high-resolution spectra. It remains approximately valid in a slightly broader range. When the relation is inverted, the error in true metallicity as derived from KIC is (0.25 dex)/0.43–0.6 dex. We thereby quantitatively confirm the cautionary note by Brown et al. that KIC estimates of [Fe/H] should not be used by "anyone with a particular interest in stellar metallicities". Fortunately, many more LAMOST spectroscopic metallicities will be available in the near future.