Li Distribution, Kinematics, and Detailed Abundance Analysis among Very Metal-poor Stars in the Galactic Halo from the HESP-GOMPA Survey
نویسندگان
چکیده
We present a study on the detailed elemental abundances of newly identified bright very metal-poor stars with detection lithium, initially observed as part SDSS/MARVELS pre-survey. These were selected for high-resolution spectroscopic follow-up HESP-GOMPA survey. In this work, we discuss Li detected several in survey, which include main-sequence stars, subgiants, and red giants. Different classes are found to exhibit similar distributions Li, point towards common origin. derive scaling relation depletion function temperature giants stars; majority samples from literature fall within 1sigma (0.19 0.12 dex/K dwarfs respectively) relationship. also report existence slope distances Galactic plane, indicating mixed stellar populations. Most Li-rich be or close galactic plane. Along have derived C, odd-Z, alpha-, Fe-peak, neutron-capture elements each star. used astrometric parameters Gaia-EDR3 complement our study, kinematics differentiate between motions those formed situ accreted. The population Spite plateau, including additional literature, is significant contributions through accretion. orbits program been studied period 5 Gyr backward time.
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2022
ISSN: ['2041-8213', '2041-8205']
DOI: https://doi.org/10.3847/1538-4357/ac8b0f