LAMOST DR1: Stellar parameters and chemical abundances with SP_Ace

TL;DR

This paper analyzes the LAMOST DR1 spectral database using the SP_Ace code to derive stellar parameters and chemical abundances for over a million stars, validating results against high-resolution surveys.

Contribution

It introduces a new analysis method with SP_Ace for large spectral datasets, providing reliable stellar parameters with quantified errors and systematic error discussion.

Findings

Derived stellar parameters for over 1 million stars.

Achieved typical errors: ~120 K in T_eff, 0.2 in log(g), 0.15 dex in [Fe/H], 0.1 dex in [$ ext{α}$/Fe].

Catalog is publicly available for community use.

Abstract

We present a new analysis of the LAMOST DR1 survey spectral database performed with the code SP_Ace, which provides the derived stellar parameters T$_{\rm eff}$, log (g), [Fe/H], and [$\alpha$/Fe] for 1,097,231 stellar objects. We tested the reliability of our results by comparing them to reference results from high spectral resolution surveys. The expected errors can be summarized as $\sim$120 K in T$_{\rm eff}$, $\sim$0.2 in log (g), $\sim$0.15 dex in [Fe/H], and $\sim$0.1 dex in [$\alpha$/Fe] for spectra with S/N$>$40, with some differences between dwarf and giant stars. SP_Ace provides error estimations consistent with the discrepancies observed between derived and reference parameters. Some systematic errors are identified and discussed. The resulting catalog is publicly available at the LAMOST and CDS websites.