Ref: ASTROimport-301

On the Metallicities of Kepler Stars

Dong, S. ; Zheng, Z. ; Zhu, Z. ; De Cat, P. ; Fu, J. N. ; Yang, X. H. ; Zhang, H. ; Jin, G. ; Zhang, Y.

published in The Astrophysical Journal, 789, pp. L3 (2014)

Abstract: 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.

DOI: 10.1088/2041-8205/789/1/L3
Links: link

The record appears in these collections:
Royal Observatory of Belgium > Astronomy & Astrophysics
Science Articles > Peer Reviewed Articles

 Record created 2016-07-01, last modified 2016-07-06