Lithium-rich Giants in LAMOST Survey. I. The Catalog

Abstract

Standard stellar evolution model predicts a severe depletion of lithium (Li) abundance during the first dredge up process (FDU). Yet a small fraction of giant stars are still found to preserve a considerable amount of Li in their atmospheres after the FDU. Those giants are usually identified as Li-rich by a widely used criterion, A (Li) > 1.5 dex. A large number of works dedicated to searching for and investigating this minority of the giant family, and the amount of Li-rich giants, has been largely expanded on, especially in the era of big data. In this paper, we present a catalog of Li-rich giants found from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) survey with Li abundances derived from a template-matching method developed for LAMOST low-resolution spectra. The catalog contains 10,535 Li-rich giants with Li abundances from ∼1.5 to ∼4.9 dex. We also confirm that the ratio of Li-rich phenomenon among giant stars is about 1%—or more specifically, 1.29%—from our statistically important sample. This is the largest Li-rich giant sample ever reported to date, which significantly exceeds amount of all reported Li-rich giants combined. The catalog will help the community to better understand the Li-rich phenomenon in giant stars.