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Related papers: NGC 7789: An Open Cluster Case Study

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We provide the whole set of Lick indices from CN1 to TiO2 of Simple Stellar Population models with, for the first time, variable element abundance ratios, [alpha/Fe]=0.0, 0.3, 0.5, [alpha/Ca]=-0.1, 0.0, 0.2, 0.5, and [alpha/N]=-0.5, 0.0.…

Astrophysics · Physics 2009-11-07 Daniel Thomas , Claudia Maraston , Ralf Bender

Recent observations have shown that a growing number of the most massive Galactic globular clusters contain multiple populations of stars with different [Fe/H] and neutron-capture element abundances. NGC 6273 has only recently been…

Reconstructing the Galactic evolution of lithium (Li) is the main tool used to constrain the source(s) of Li enrichment in the Galaxy. Recent results have suggested a decline in Li at supersolar metallicities, which may indicate reduced…

Chemical elements in the hot medium permeating early-type galaxies, groups, and clusters make them an excellent laboratory for studying metal enrichment and cycling processes in the largest scales of the universe. Here, we report the…

Astrophysics of Galaxies · Physics 2023-08-10 Kotaro Fukushima , Shogo B. Kobayashi , Kyoko Matsushita

We present new accurate abundances for five neutron-capture (Y, La, Ce, Nd, Eu) elements in 73 classical Cepheids located across the Galactic thin disk. Individual abundances are based on high spectral resolution (R ~ 38,000) and high…

Here we present results from over 500 kiloseconds Chandra and XMM-Newton observations of the cool core of the Centaurus cluster. We investigate the spatial distributions of the O, Mg, Si, S, Ar, Ca, Cr, Mn, Fe, and Ni abundances in the…

Astrophysics of Galaxies · Physics 2022-07-01 Kotaro Fukushima , Shogo B. Kobayashi , Kyoko Matsushita

We present an analysis of the multiple stellar populations of the globular cluster NGC 1851. We used lower resolution spectra of giant stars to measure CN, CH, and calcium H & K spectral indices, and determine elemental abundances for…

Solar and Stellar Astrophysics · Physics 2016-10-31 Jeffrey D. Simpson , Sarah L. Martell , Colin A. Navin

We carried out a homogeneous abundance study for various elements, including $\alpha$-elements, iron peak elements and $n$-capture elements for 35 metal-poor stars with a wide metallicity range ($-3.0\lesssim$[Fe/H]$\lesssim-0.5$).…

Astrophysics · Physics 2008-06-02 Jeong-Deok Lee , Sang-Gak Lee , Kang-Min Kim

We present a detailed abundance analysis of 8 stars selected as extremely metal poor candidates from the Hamburg/ESO Survey (HES). For comparison, we have also analysed 3 extremely metal-poor candidates from the HK survey, and 3 additional…

We present the results of an analysis for 107 extremely metal-poor (EMP) stars with metallicities less than [Fe/H] = -3.0, identified from medium-resolution spectra in SDSS. We follow a methodology based on comparisons of the observed…

Solar and Stellar Astrophysics · Physics 2016-09-07 E. Fernandez-Alvar , C. Allende Prieto , T. C. Beers , Y. S. Lee , T. Masseron , D. P. Schneider

Metal-rich globular clusters trace the formation of bulges. Abundance ratios in the metal-rich globular clusters such as NGC 6553 can constrain the formation timescale of the Galactic bulge. The purpose of this study is determine the…

We measure chemical abundances for over 20 elements of 15 N-rich field stars with high resolution ($R \sim 30000$) optical spectra. We find that Na, Mg, Al, Si, and Ca abundances of our N-rich field stars are mostly consistent with those of…

Astrophysics of Galaxies · Physics 2021-06-02 Jincheng Yu , Baitian Tang , J. G. Fernandez-Trincado , Douglas Geisler , Hongliang Yan , M. Soto

The [Sr/Ba] and [Y/Ba] scatter observed in some galactic halo stars that are very metal-poor stars and in a few individual stars of the oldest known Milky Way globular cluster NGC 6522,have been interpreted as evidence of early enrichment…

Solar and Stellar Astrophysics · Physics 2015-06-22 B. Barbuy , C. Chiappini , E. Cantelli , E. Depagne , M. Pignatari , R. Hirschi , G. Cescutti , S. Ortolani , V. Hill , M. Zoccali , D. Minniti , M. Trevisan , E. Bica , A. Gómez

We present abundance ratios for 23 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 M71. The analyzed spectra, obtained with HIRES at…

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

Context: Open clusters are very useful targets for examining possible trends in galactocentric distance and age, especially when young and old open clusters are compared. Aims: We carried out a detailed spectroscopic analysis to derive the…

Solar and Stellar Astrophysics · Physics 2015-06-15 O. J. Katime Santrich , C. B. Pereira , N. A. Drake

By using the multifiber spectrograph FLAMES mounted at the ESO-VLT, we have obtained high-resolution spectra for 18 giant stars, belonging to 3 old globular clusters of the Large Magellanic Cloud (namely NGC 1786, 2210 and 2257). While…

Solar and Stellar Astrophysics · Physics 2009-11-13 A. Mucciarelli , L. Origlia , F. R. Ferraro , E. Pancino

The Gaia-ESO Survey (GES) is a large public spectroscopic survey that was carried out using the multi-object FLAMES spectrograph at the Very Large Telescope. The survey provides accurate radial velocities, stellar parameters, and elemental…

We present detailed elemental abundances and radial velocities of stars in the metal-poor globular cluster (GC) NGC 2298, based on near-infrared high-resolution ($R\sim$ 22,500) spectra of twelve members obtained during the second phase of…

The location of the Scutum Red-Supergiant (RSG) clusters at the end of the Galactic Bar makes them an excellent probe of the Galaxy's secular evolution; while the clusters themselves are ideal testbeds in which to study the predictions of…

We derive [Cu/Fe] for 117 giant stars in ten globular clusters (M3, M4, M5, M10, M13, M15, M71, NGC 7006, NCG 288, and NGC 362) and find that globular cluster Cu abundances appear to follow [Cu/Fe] trends found in the field. This result is…