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Related papers: Abundance ratios in GALAH DR2 and their implicatio…

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We report on the very low $\alpha$-element abundances of a group of metal-poor stars with high orbital energy and with large retrograde motion in the Milky Way halo, whose excess has been reported recently from metallicity and kinematics.…

Astrophysics of Galaxies · Physics 2019-04-17 Tadafumi Matsuno , Wako Aoki , Takuma Suda

We present argon abundances from a sample of 46 star-forming galaxies at $z=2-3.5$ from the Assembly of Ultradeep Rest-Optical Observations Revealing Astrophysics (AURORA) program. Although argon is an $\alpha-$element produced by Core…

The relative abundances of the Fe-peak elements (Ti-Zn) at the lowest metallicities are intimately linked to the physics of core-collapse supernova explosions. With a sample of 25 very metal-poor damped Lyman-alpha systems, we investigate…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Ryan Cooke , Max Pettini , Regina A. Jorgenson , Michael T. Murphy , Gwen C. Rudie , Charles C. Steidel

Open cluster members are coeval and share the same initial bulk chemical compositions. Consequently, differences in surface abundances between members of a cluster that are at different evolutionary stages can be used to study the effects…

Recent studies suggest that chemical abundances hold the key to disentangling halo substructure, providing a more reliable tracer than dynamics alone. We aim to probe the Milky Way stellar halo using high-dimensional chemical abundances…

Astrophysics of Galaxies · Physics 2026-04-08 Milan Quandt-Rodriguez , Sara Lucatello , Lorenzo Spina , Mario Pasquato , Marco Canducci

Recent theoretical yields and chemical evolution models demonstrate that intermediate-mass AGB stars cannot reproduce the observed abundance distributions of O, Na, Mg, and Al. As a further observational test of this finding, we present…

We discuss the characteristics of known extremely metal-poor (EMP) stars in the Galaxy using the Stellar Abundances for Galactic Archaeology (SAGA) database (Suda et al. 2008, PASJ, 60, 1159).The analyses of carbon-enhanced stars in our…

Astrophysics of Galaxies · Physics 2015-05-20 Takuma Suda , Shimako Yamada , Yutaka Katsuta , Yutaka Komiya , Chikako Ishizuka , Wako Aoki , Masayuki Y. Fujimoto

Recent work has shown that most globular clusters have at least two chemically distinct components, as well as cluster-to-cluster differences in the mean [O/Fe], [Mg/Fe], and [Si/Fe] ratios at similar [Fe/H] values. In order to investigate…

Solar and Stellar Astrophysics · Physics 2015-06-05 Don A. VandenBerg , Peter A. Bergbusch , Aaron Dotter , Jason W. Ferguson , Georges Michaud , Jacques Richer , Charles Proffitt

Atmospheric parameters and chemical compositions for ten stars with metallicities in the region of -2.2< [Fe/H] <-0.6 were precisely determined using high resolution, high signal to noise, spectra. For each star the abundances, for 14 to 27…

Modern tools for modeling stellar evolution, such as MESA (Modules for Experiments in Stellar Astrophysics), offer state-of-the-art implementations of stellar theories. However, this parametric approach introduces many free parameters that…

Solar and Stellar Astrophysics · Physics 2026-02-10 O. Ziółkowska , R. Smolec , A. Thoul , R. Singh Rathour , V. Hocdé

We present a new version of the compiled catalogue of nearby stars for which was published the spectoscopically determined effective temperatures, surface gravities, and abundances of iron, magnesium, calcium, silicon, and titanium.…

Astrophysics · Physics 2007-10-25 T. V. Borkova , M. S. Katchieva , B. A. Marsakov , D. M. Pitkina

We calculate nucleosynthesis in core-collapse explosions of massive Pop III stars, and compare the results with abundances of metal-poor halo stars to constrain the parameters of Pop III supernovae. We focus on iron-peak elements and, in…

Astrophysics · Physics 2011-02-11 Hideyuki Umeda , Ken'ichi Nomoto

Context: Deep GALEX UV data show that the extreme outskirts of some spiral galaxies are teeming with star formation. Such young stellar populations evolving so far away from the bulk of their host galaxies challenge our overall…

Astrophysics of Galaxies · Physics 2020-02-05 Leire Beitia-Antero , Ana Inés Gómez de Castro , Raúl de la Fuente Marcos

We present measurements of [Fe/H] for six M supergiant stars and three giant stars within 0.5 pc of the Galactic Center (GC) and one M supergiant star within 30 pc of the GC. The results are based on high-resolution (lambda / Delta lambda…

We present the iron abundance and abundance ratios for 18 elements with respect to Fe in a sample of stars with a wide range in luminosity from luminous giants to stars near the turnoff in the globular cluster M5. The analyzed spectra,…

Astrophysics · Physics 2009-11-07 Solange V. Ramirez , Judith G. Cohen

Stellar abundance measurements are subject to systematic errors that induce extra scatter and artificial correlations in elemental abundance patterns. We derive empirical calibration offsets to remove systematic trends with surface gravity…

Globular clusters (GCs) are key to understanding the formation and evolution of our Galaxy. While the abundances of light and Fe-peak elements in GCs have been widely studied, investigations into heavier, neutron-capture elements -- and…

As an investigation of the origin of ``$\alpha$-poor'' halo stars, we analyze kinematic and abundance data for 73 intermediate metallicity stars ($-1 >$ [Fe/H] $\geq -2$) selected from Paper I of this series. We find evidence for a…

Astrophysics · Physics 2009-12-08 Jon P. Fulbright

Comoving pairs, even at the separations of $\mathcal{O}(10^6)\,$AU, are a predicted reservoir of conatal stars. We present detailed chemical abundances of 62 stars in 31 comoving pairs with separations of $10^2 - 10^7\,$AU and 3D velocity…

Solar and Stellar Astrophysics · Physics 2021-11-17 Tyler Nelson , Yuan-Sen Ting , Keith Hawkins , Alexander Ji , Harshil Kamdar , Kareem El-Badry

Abundances of alpha-elements such as Ca and Mg in disk and halo stars are usually derived from equivalent widths lines measured on high resolution spectra, and assuming Local Thermodynamic Equilibrium (LTE) . In this paper, we present…

Astrophysics · Physics 2009-10-31 T. Idiart , F. Thevenin