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Related papers: Complexity on Small Scales III: Iron and alpha Ele…

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We present elemental abundances for 855 red giant branch (RGB) stars in the globular cluster Omega Centauri (w Cen) from spectra obtained with the Blanco 4m telescope and Hydra multifiber spectrograph. The sample includes nearly all RGB…

Solar and Stellar Astrophysics · Physics 2015-05-19 Christian I. Johnson , Catherine A. Pilachowski

We study the enrichment histories for nine elements, C, four alpha-elements of Mg, Si, Ca, and Ti, Sc, and three iron-peak elements of Co, Ni, and Zn, by using a large number of stellar data, collected by the Stellar Abundances for Galactic…

Astrophysics of Galaxies · Physics 2015-06-17 Shimako Yamada , Takuma Suda , Yutaka Komiya , Wako Aoki , Masayuki Y. Fujimoto

Near infrared spectra were obtained for 117 red giants in the Fornax dwarf spheroidal galaxy with the FORS1 spectrograph on the VLT, in order to study the metallicity distribution of the stars and to lift the age-metallicity degeneracy of…

Astrophysics · Physics 2009-11-10 Frederic Pont , Robert Zinn , Carme Gallart , Eduardo Hardy , Rebeccah Winnick

We use abundances of Ca, O, Na, Al from high resolution UVES spectra of 200 red giants in 17 globular clusters (GCs) to investigate the correlation found by Lee et al. (2009) between chemical enrichment from SN II and star-to-star…

We present a chemical abundance distribution study in 14 $\alpha$, odd-Z, even-Z, light, and Fe-peak elements of approximately 3200 intermediate metallicity giant stars from the APOGEE survey. The main aim of our analysis is to explore the…

Astrophysics of Galaxies · Physics 2016-03-02 Keith Hawkins , Paula Jofre , Thomas Masseron , Gerry Gilmore

High resolution, high S/N spectra have been obtained for a sample of 90 F and G main-sequence disk stars covering the metallicity range -1.0 < [Fe/H] < +0.1, and have been analysed in a parallel way to the work of Edvardsson et al. (1993).…

Astrophysics · Physics 2009-10-31 Y. Q. Chen , P. E. Nissen , G. Zhao , H. W. Zhang , T. Benoni

We investigate the intrinsic scatter in the chemical abundances of a sample of metal-poor ([Fe/H]<-2.5) Milky Way halo stars. We draw our sample from four historic surveys and focus our attention on the stellar Mg, Ca, Ni, and Fe…

Astrophysics of Galaxies · Physics 2020-11-04 Louise Welsh , Ryan Cooke , Michele Fumagalli

We present chemical abundances for Mg, Si, Ca and Fe for three red giants in the sparse globular cluster Terzan 7, physically associated to the Sagittarius Dwarf Spheroidal Galaxy (Sgr dSph), which is presently being tidally disrupted by…

Astrophysics · Physics 2007-05-23 L. Sbordone , P. Bonifacio , G. Marconi , R. Buonanno

We have re-evaluated empirical expressions for the abundance determination of N, O, Ne, S, Cl, Ar and Fe taking into account the latest atomic data and constructing an appropriate grid of photoionization models with state-of-the art model…

Astrophysics · Physics 2009-07-28 Y. I. Izotov , G. Stasinska , G. Meynet , N. G. Guseva , T. X. Thuan

We present equivalent widths, improved model atmosphere parameters, and revised abundances for 14 species of 11 elements derived from high resolution optical spectroscopy of 311 metal-poor stars. All of these stars had their parameters…

Solar and Stellar Astrophysics · Physics 2025-02-27 Sanil Mittal , Ian U. Roederer

High-resolution spectra of 13 core helium-burning stars in the thick disk of the Galaxy have been obtained with the SOFIN spectrograph on the Nordic Optical Telescope to investigate abundances of up to 22 chemical elements. Abundances of…

Astrophysics · Physics 2009-11-07 G. Tautvaisiene , B. Edvardsson , I. Tuominen , I. Ilyin

We have made observations with the Keck I telescope and HIRES at a resolution of $\sim$45,000 of five nearly identical stars at the turn-off of the metal-rich globular cluster M 71. Our mean Fe abundance, [Fe/H]=-0.80 +-0.02, is in…

Dwarf irregular galaxies appear to have undergone very slow chemical evolution since they have low nebular abundances, but have had ongoing star formation over the past 15 Gyr. They are too distant for red giant abundance analyses to…

Astrophysics · Physics 2007-05-23 Kim Venn , Eline Tolstoy , Andreas Kaufer , Rolf Peter Kudritzki

We constrain the iron abundance in a sample of 33 low-ionization Galactic planetary nebulae (PNe) using [Fe III] lines and correcting for the contribution of higher ionization states with ionization correction factors (ICFs) that take into…

Astrophysics · Physics 2011-02-18 G. Delgado-Inglada , M. Rodriguez , A. Mampaso , K. Viironen

The thin red giant branch (RGB) of the Carina dwarf spheroidal galaxy appears at first sight quite puzzling and seemingly in contrast with the presence of several distinct bursts of star formation. In this Letter, we provide a measurement…

Astrophysics · Physics 2009-11-07 L. Rizzi , E. V. Held , G. Bertelli , I. Saviane

In spite of many observational efforts aiming to characterize the chemical evolution of our Galaxy, not much is known about the origin of fluorine (F). Models suggest that the F found in the Galaxy might have been produced mainly in three…

Astrophysics of Galaxies · Physics 2015-06-03 A. Recio-Blanco , P. de Laverny , C. Worley , N. C. Santos , C. Melo , G. Israelian

Parameters and abundances for 1002 stars of spectral types F, G, and K of luminosity class IV and V have been derived. After culling the sample for rotational velocity and effective temperature, 867 stars remain for discussion. Twenty-eight…

Solar and Stellar Astrophysics · Physics 2016-12-28 R. Earle Luck

We present chemical abundances and velocities of five stars between 0.3 kpc to 1.1 kpc from the center of the Tucana II ultra-faint dwarf galaxy (UFD) from high-resolution Magellan/MIKE spectroscopy. We find that every star is deficient in…

We report abundance analysis for 6 M giant members of the old open cluster NGC6791, based on infrared spectroscopy (1.5-1.8 micron) at R=25,000, using the NIRSPEC spectrograph at the Keck II telescope. We find the iron abundance <[Fe/H]>=…

Astrophysics · Physics 2009-11-11 L. Origlia , E. Valenti , R. M. Rich , F. R. Ferraro

Extremely metal-poor stars are keys to understand the early evolution of our Galaxy. The ESO large programme TOPoS has been tailored to analyse a new set of metal-poor turn-off stars, whereas most of the previously known extremely…

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