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Related papers: The Carina Project. VIII. The {\alpha}-element abu…

200 papers

We present new BV time series data of the Carina dwarf spheroidal galaxy. Current data cover an area of about 0.3 square degrees around the center of the galaxy and allowed us to identify 92 variables. Among them 75 are RR Lyrae stars, 15…

We study the chemodynamical properties of the Carina dwarf spheroidal by combining an intermediate spectroscopic resolution dataset of more than 900 red giant and red clump stars, with high-precision photometry to derive the atmospheric…

Astrophysics of Galaxies · Physics 2016-02-17 G. Kordopatis , N. C. Amorisco , N. W. Evans , G. Gilmore , S. E. Koposov

We report the first high resolution, detailed abundances of 21 elements for giants in the Galactic bulge/bar within $1^\circ$ of the Galactic plane, where high extinction has rendered such studies challenging. Our high S/N and…

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

In the framework of an ESO Large Programme high quality spectra of 70 very metal-poor dwarfs and giants were obtained with the VLT-UVES combination. This paper reports the detailed analyses of the 35 giants of the sample. At the exception…

Stellar parameters and abundances provide crucial insights into stellar and Galactic evolution studies. In this work, we developed a convolutional neural network (CNN) to estimate stellar parameters: effective temperature…

Astrophysics of Galaxies · Physics 2025-06-23 Haoyang Liu , Cuihua Du , Mingji Deng , Jian Zhang

The study of open-cluster chemical abundances provides insights on stellar nucleosynthesis processes and on Galactic chemo-dynamical evolution. In this paper we present an extended abundance analysis of 10 species (Fe, Ni, Cr, V, Sc, Si,…

We present photometry for stars in the Carina dwarf spheroidal galaxy that is unprecedented in depth, accuracy and spatial coverage. Our data demonstrate that Carina has had a surprisingly complex evolution dominated by episodic bursts of…

Astrophysics · Physics 2007-05-23 T. A. Smecker-Hane , P. B. Stetson , J. E. Hesser , D. A. VandenBerg

We present results of high resolution (~ 55000) spectral observations of 830 photometrically pre-selected candidate red giants in the magnitude range of V = 9-12. We develop a pipeline for automated determination of the stellar atmospheric…

Solar and Stellar Astrophysics · Physics 2015-05-20 Dmitry Bizyaev , Verne V. Smith , Katia Cunha

We present chemical abundances in a sample of luminous cool stars located within 30 pc of the Galactic Center. Abundances of carbon, nitrogen, oxygen, calcium, and iron were derived from high-resolution infrared spectra in the H- and…

We present a detailed chemical abundance study of evolved stars in 10 open clusters based on Hydra multi-object echelle spectra obtained with the WIYN 3.5m telescope. From an analysis of both equivalent widths and spectrum synthesis,…

Astrophysics of Galaxies · Physics 2015-05-28 H. R. Jacobson , C. A. Pilachowski , E. D. Friel

The mean stellar alpha-to-iron abundance ratio ([$\alpha$/Fe]) of a galaxy is an indicator of galactic star formation timescale. It is important for understanding the star formation history of early-type galaxies (ETGs) as their star…

Astrophysics of Galaxies · Physics 2020-08-25 Yiqing Liu

Symbiotic stars (SySt) are binaries composed of a star in the later stages of evolution and a stellar remnant. The enhanced mass-loss from the giant drives interacting mass exchange and makes these systems laboratories for understanding…

Solar and Stellar Astrophysics · Physics 2017-01-04 Cezary Galan , Joanna Mikolajewska , Kenneth H. Hinkle , Richard R. Joyce

Determining elemental abundances of bulge stars can, via chemical evolution modeling, help to understand the formation and evolution of the bulge. Recently there have been claims both for and against the bulge having a different…

Astrophysics of Galaxies · Physics 2017-02-08 H. Jönsson , N. Ryde , M. Schultheis , M. Zoccali

We have obtained high-res, high S/N ratio CCD echelle spectra of 10 bright red giants in 3 GCs (47Tuc, NGC6752 and NGC6397) roughly spanning the range of metallicities of the galactic GC system; they reveal no evidence of star to star…

Astrophysics · Physics 2009-07-28 E. Carretta , R. G. Gratton

(abbreviated) We used HAWK-I at the ESO VLT to produce a near-infrared survey of the Carina Nebula that is deep enough to detect the full low-mass stellar population. The results of a recent deep X-ray survey are used to distinguish between…

A previous study (Nissen & Schuster 2010) of 94 dwarf stars with -1.6 < [Fe/H] < -0.4 has revealed the existence of two distinct halo populations with a systematic difference in [alpha/Fe] at a given metallicity. In continuation of that…

Astrophysics of Galaxies · Physics 2015-05-27 Poul E. Nissen , William J. Schuster

We have determined carbon abundances or upper limits from the forbidden [C I] line at 8727.13 A for 85 F and early G type main sequence stars, with metallicities ranging between [Fe/H] = -1.0 and [Fe/H] = +0.25. The [C I] line has not been…

Astrophysics · Physics 2007-05-23 Helena Andersson , Bengt Edvardsson

Using high-resolution spectroscopy, we provide a determination of [Fe/H] and [Ca/H] for confirmed red-giant branch member stars of the Hercules dwarf spheroidal galaxy. Based on this we explore the ages of the prevailing stellar populations…

Astrophysics of Galaxies · Physics 2015-05-20 D. Adén , K. Eriksson , S. Feltzing , E. K. Grebel , A. Koch , M. I. Wilkinson

Spectral data on early type galaxies is analyzed for chemical abundance with an emphasis on obtaining detailed abundances for the elements O and Si in addition to C, N, Na, Mg, Ca, Fe, and Ba. The abundance trends with velocity dispersion…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Guy Worthey , Baitian Tang , Jedidiah Serven