SIMBAD references

2020ApJ...903...88M - Astrophys. J., 903, 88-88 (2020/November-2)

Cosmological insights into the early accretion of r-process-enhanced stars. I. A comprehensive chemodynamical analysis of LAMOST J1109+0754.

MARDINI M.K., PLACCO V.M., MEIRON Y., ISHCHENKO M., AVRAMOV B., MAZZARINI M., BERCZIK P., ARCA SEDDA M., BEERS T.C., FREBEL A., TAANI A., DONNARI M., AL-WARDAT M.A. and ZHAO G.

Abstract (from CDS):

This study presents a comprehensive chemodynamical analysis of LAMOST J1109+0754, a bright (V = 12.8), extremely metal-poor ([Fe/H] = -3.17) star, with a strong r-process enhancement ([Eu/Fe] = +0.94 ± 0.12). Our results are based on the 7D measurements supplied by Gaia and the chemical composition derived from a high-resolution (R ∼ 110,000), high signal-to-noise ratio (S/N∼60) optical spectrum obtained by the 2.4 m Automated Planet Finder Telescope at Lick Observatory. We obtain chemical abundances of 31 elements (from lithium to thorium). The abundance ratios ([X/Fe]) of the light elements (Z <= 30) suggest a massive Population III progenitor in the 13.4-29.5 M☉ mass range. The heavy-element (30 < Z <= 90) abundance pattern of J1109+075 agrees extremely well with the scaled-solar r-process signature. We have developed a novel approach to trace the kinematic history and orbital evolution of J1109+0754 with a cOsmologically deRIved timE-varyiNg Galactic poTential (the ORIENT) constructed from snapshots of a simulated Milky Way analog taken from the Illustris-TNG simulation. The orbital evolution within this Milky Way-like galaxy, along with the chemical abundance pattern, implies that J1109+0754 likely originated in a low-mass dwarf galaxy located ∼60 kpc from the center of the Galaxy, which was accreted ∼6-7 Gyr ago, and that the star now belongs to the outer-halo population.

Abstract Copyright: © 2020. The American Astronomical Society. All rights reserved.

Journal keyword(s): Chemically peculiar stars - Population III stars - R-process - Stellar kinematics - Chemical abundances - Stellar dynamics - Orbits - Galaxy dynamics

VizieR on-line data: <Available at CDS (J/ApJ/903/88): table2.dat>

Simbad objects: 6

goto Full paper

goto View the references in ADS

To bookmark this query, right click on this link: simbad:2020ApJ...903...88M and select 'bookmark this link' or equivalent in the popup menu