Additionally, in the stellar evolutionary model, many AGB (asymptotic giant branch) stars have been found to have higher Li levels. This is probably because of the higher luminosity of red giants as compared to main-sequence stars, not necessarily a result of higher frequency in red giants. Li-rich stars are much more commonly detected in red giant stars. Mechanisms for Lithium Enrichment in Stars The Li content was determined using spectroscopic analysis, and standard abundance analysis was carried out using local thermodynamic equilibrium (LTE) and checked against nonlocal thermodynamic equilibrium (NLTE) model stellar photospheres. All of the stars have larger than expected excesses of lithium (Li), and one star has more than 100 times higher Li abundance than the normally expected values, which is the largest excess in such metal-poor stars known to date.
In a recent paper published in the Astrophysical Journal Letters, 1 a team of Chinese and Japanese astronomers reported on high-lithium concentrations in 12 newly discovered low-mass, metal-poor, 2 main-sequence, and red giant stars in the Milky Way halo.
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