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Related papers: Carbon in the Draco Dwarf Spheroidal Galaxy

200 papers

The photometric study of the Sagittarius dwarf galaxy by Marconi et al (1998) has suggested the presence of a spread in metallicity (-0.7< [Fe/H] < -1.6), which may result from different bursts of star formation. We present the results from…

Astrophysics · Physics 2019-08-17 G. Marconi , P. Bonifacio , L. Pasquini , P. Molaro

The abundances of carbon, oxygen, and iron in late-type stars are important parameters in exoplanetary and stellar physics, as well as key tracers of stellar populations and Galactic chemical evolution. We carried out three-dimensional (3D)…

Solar and Stellar Astrophysics · Physics 2019-10-09 A. M. Amarsi , P. E. Nissen , Á. Skúladóttir

We use previously-published moderate-resolution spectra in combination with stellar atmosphere models to derive the first measured chemical abundance ratios in the Leo II dSph galaxy. We find that for spectra with SNR > 24, we are able to…

Astrophysics · Physics 2009-11-13 Matthew Shetrone , Michael H. Siegel , David O. Cook , Tammy Bosler

Context: Classical Cepheids can be adopted to trace the chemical evolution of the Galactic disk since their distances can be estimated with very high accuracy. Aims: Homogeneous iron abundance measurements for 33 Galactic Cepheids located…

Astrophysics · Physics 2009-11-13 B. Lemasle , P. Francois , A. Piersimoni , S. Pedicelli , G. Bono , C. D. Laney , F. Primas , M. Romaniello

We present radial velocities and [Fe/H] abundances for 340 stars in the Fornax dwarf spheroidal from R~16,000 spectra. The targets have been obtained in the outer parts of the galaxy, a region which has been poorly studied before. Our…

Astrophysics of Galaxies · Physics 2014-12-03 Benjamin Hendricks , Andreas Koch , Matthew Walker , Christian I. Johnson , Jorge Penarrubia , Gerard Gilmore

We develop and test a method for the estimation of metallicities ([Fe/H]) and carbon abundance ratios ([C/Fe]) for carbon-enhanced metal-poor (CEMP) stars, based on application of artificial neural networks, regressions, and synthesis…

Chemical abundances of 26 metal-poor dwarfs and giants are determined from high-resolution and high signal-to-noise ratio spectra obtained with Subaru/HDS. The sample is selected so that most of the objects have outer-halo kinematics.…

Astrophysics of Galaxies · Physics 2009-11-18 Lan Zhang , Miho Ishigaki , Wako Aoki , Gang Zhao , Masashi Chiba

We report on the chemical abundances of stars in the Carina dwarf spheroidal galaxy (dSph) derived from low-resolution spectra. We have determined values of [Fe/H] for 52 stars from the reduced equivalent width of the Ca II infrared triplet…

We have undertaken the study of the elemental abundances and kinematic properties of a metal-poor sample of candidate thick-disk stars selected from the RAVE spectroscopic survey of bright stars to differentiate among the present scenarios…

We present a detailed study of the composition of 20 M giants in the Galactic center with 15 of them confirmed to be in the Nuclear Star Cluster. As a control sample we have also observed 7 M giants in the Milky Way Disk with similar…

Abundances for Fe, O, and the alpha-elements (Mg, Si, Ca, and Ti) have been derived from high resolution spectra of a sample of about one hundred dwarfs with high precision parallaxes measured by HIPPARCOS. The stars have metal abundances…

Astrophysics · Physics 2007-05-23 R. G. Gratton , E. Carretta , G. Clementini , C. Sneden

We present a new survey for CO in dwarf galaxies using the Kitt Peak 12m telescope. We observed the central regions of 121 northern dwarfs with IRAS detections and no known CO emission. We detect CO in 28 of these galaxies and marginally…

Astrophysics · Physics 2009-11-10 Adam Leroy , Alberto D. Bolatto , Joshua D. Simon , Leo Blitz

A few dozen dwarf satellite galaxies of the Milky Way have been discovered, which are often viewed as the remaining building blocks of our Galaxy. The follow-up spectroscopy showed that dwarf galaxies have a sizeable spread in their…

Astrophysics of Galaxies · Physics 2020-02-24 Sang-Il Han , Hak-Sub Kim , Suk-Jin Yoon , Young-Wook Lee , Nobuo Arimoto , Sakurako Okamoto , Chang H. Ree

We present an analysis of high-resolution Keck/HIRES spectroscopic observations of J0815+4729, an extremely carbon-enhanced, iron-poor dwarf star. These high-quality data allow us to derive a metallicity of [Fe/H]$=-5.49{\pm}0.14$ from the…

Solar and Stellar Astrophysics · Physics 2020-04-22 Jonay I. González Hernández , David S. Aguado , Carlos Allende Prieto , Adam J. Burgasser , Rafael Rebolo

The population of cool carbon (C) stars located far from the galactic plane is probably made of debris of small galaxies such as the Sagittarius dwarf spheroidal galaxy (Sgr), which are disrupted by the gravitational field of the Galaxy. We…

Astrophysics of Galaxies · Physics 2015-06-18 Nicolas Mauron , Kamo S. Gigoyan , Paul Berlioz-Arthaud , Alain Klotz

In this paper, we present low resolution (R=500) near-infrared spectra for selected and serendipitous sources in six inner in-plane Galactic fields, with the aim of analysing the stellar content present. From the equivalent widths of the…

Astrophysics · Physics 2009-11-13 C. González-Fernández , A. Cabrera-Lavers , P. L. Hammersley , F. Garzón

In this paper we present the results of observations of seventeen HII regions in thirteen galaxies from the SIGRID sample of isolated gas rich irregular dwarf galaxies. The spectra of all but one of the galaxies exhibit the auroral [OIII]…

Astrophysics of Galaxies · Physics 2015-06-19 David C. Nicholls , Michael A. Dopita , Ralph S. Sutherland , Helmut Jerjen , Lisa J. Kewley , Hassan Basurah

We report on oxygen abundances determined from medium-resolution near-IR spectroscopy for a sample of 57 carbon-enhanced metal-poor (CEMP) stars selected from the Hamburg/ESO survey. The majority of our program stars exhibit oxygen-to-iron…

We present deep echelle spectrophotometry of the brightest emission-line knots of the star-forming galaxies He 2-10, Mkn 1271, NGC 3125, NGC 5408, POX 4, SDSS J1253-0312, Tol 1457-262, Tol 1924-416 and the HII region Hubble V in the Local…

Astrophysics of Galaxies · Physics 2015-06-22 C. Esteban , J. García-Rojas , L. Carigi , M. Peimbert , F. Bresolin , A. R. López-Sánchez , A. Mesa-Delgado

We present results from the analysis of 88 carbon stars selected from Hamburg/ESO (HES) survey using low-resolution spectra (R$\sim$1330 \& 2190). The spectra were obtained with the Himalayan Faint Object Spectrograph Camera (HFOSC)…

Solar and Stellar Astrophysics · Physics 2024-01-11 Meenakshi Purandardas , Aruna Goswami