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Related papers: Spatial metallicity asymmetry in $\omega$ Centauri

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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

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

We present Li, Na, Al and Fe abundances of 199 lower red giant branch stars members of the stellar system Omega Centauri, using high-resolution spectra acquired with FLAMES at the Very Large Telescope. The A(Li) distribution is peaked at…

Solar and Stellar Astrophysics · Physics 2018-10-31 A. Mucciarelli , M. Salaris , L. Monaco , P. Bonifacio , X. Fu , S. Villanova

We study the metallicity distribution and kinematic properties of 4,680 A/F/G/K-type giant stars with $|z|>$ 5 kpc selected from the LAMOST spectroscopic survey. The metallicity distribution of giant stars with 5 $<|z|\leqslant$ 15 kpc can…

Astrophysics of Galaxies · Physics 2018-08-15 Shuai Liu , Cuihua Du , Heidi Jo Newberg , Yuqin Chen , Zhenyu Wu , Jun Ma , Xu Zhou , Zihuang Cao , Yonghui Hou , Yuefei Wang , Yong Zhang

I present some preliminary results from a high-resolution spectroscopic observing campaign conducted with UVES at the ESO VLT, devoted to the study of the newly discovered, metal-rich red giant branch (RGB-a) in omega Centauri. In…

Astrophysics · Physics 2007-05-23 E. Pancino

Most of the metals (elements heavier than helium) ever produced by stars in the member galaxies of galaxy clusters currently reside within the hot, X-ray emitting intra-cluster gas. Observations of X-ray line emission from this…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Norbert Werner , Ondrej Urban , Aurora Simionescu , Steven W. Allen

We adopted uvby Stroemgren photometry to investigate the metallicity distribution of Omega Cen Red Giant (RG) stars. We provided a new empirical calibration of the Stroemgren m1 = (v-b)-(b-y) metallicity index based on cluster stars. The…

The globular cluster Omega Centauri (NGC 5139) is the most massive and brightest cluster in our Galaxy. It has also a moderately high mass to light ratio (3.6) and an anomalous flattening (0.83) for a globular cluster. This cluster is also…

Astrophysics · Physics 2007-05-23 Sergio Ortolani , Stefano Covino , Giovanni Carraro

The distributions of a galaxy's gas and stars in chemical space encodes a tremendous amount of information about that galaxy's physical properties and assembly history. However, present methods for extracting information from chemical…

Astrophysics of Galaxies · Physics 2018-02-14 Mark R. Krumholz , Yuan-Sen Ting

Compilations of abundances of Strontium and Barium in extremely metal-poor stars show that an apparent cutoff is observed for [Sr/Ba] at [Fe/H]$<$-3.6 and large fluctuations for [Fe/H]$>$-3.6 with a clear upper bound depending on…

Solar and Stellar Astrophysics · Physics 2015-06-15 Wako Aoki , Takuma Suda , Richard Boyd , Toshitaka Kajino , Michael Famiano

We present wide-field and high-precision BV and Ca & Stromgren by photometry of omega Centauri, which represents one of the most extensive photometric surveys to date for this cluster. The member stars of omega Cen are well discriminated…

Astrophysics · Physics 2009-11-10 S. -C. Rey , Y. -W. Lee , C. Ree , J. -M. Joo , Y. -J. Sohn , A. Walker

This study is aimed at identifying possible low-mass and sub-stellar companions to stars with well-determined metallicities. We investigate the multiplicity of metal-poor stars along with its impact on formation processes in the conditions…

Solar and Stellar Astrophysics · Physics 2025-01-27 N. Lodieu , A. Pérez Garrido , J. -Y. Zhang , E. L. Martín , R. Rebolo López , F. Pérez-Toledo , R. Clavero , D. Nespral

Metallicities of both gas and stars decline toward large radii in spiral galaxies, a trend known as the radial metallicity gradient. We quantify the evolution of the metallicity gradient in the Milky Way as traced by APOGEE red giants with…

We report the results of an extensive VLT high-resolution imaging campaign of the central region of the giant globular cluster omega Centauri. More than 100,000 stars have been measured in the inner 9'x 9' region of the cluster. On the…

Astrophysics · Physics 2011-07-18 A. Sollima , F. R. Ferraro , E. Pancino , M. Bellazzini

The recently published spectroscopic metallicities of RR Lyrae stars in M3 (Sandstrom, K., Pilachowski, C. A., and Saha, A. 2001, AJ 122, 3212) though show a relatively wide range of the [Fe/H] values, the conclusion that no metallicity…

Astrophysics · Physics 2009-11-07 Johanna Jurcsik

Stellar metallicity encodes the integrated effects of gas inflow, star formation, and feedback-driven outflow, yet its connection to galaxy structure remains poorly understood. Using SDSS-IV MaNGA, we present the direct observational…

Astrophysics of Galaxies · Physics 2025-10-06 Kai Wang

RR Lyrae stars are excellent tracers of stellar populations for old, metal-poor components in the Milky Way Galaxy and the Local Group. Their luminosities have a metallicity-dependence, but determining spectroscopic [Fe/H] metallicities for…

To determine the nature of the recently discovered, ring-like stellar structure at the Galactic anticenter, we have collected spectra of a set of presumed constituent M giants selected from the 2MASS point source catalog. Radial velocities…

We interpret the stellar population of $\omega$ Centauri by means of a population synthesis analysis, following the most recent observational guidelines for input metallicities, helium and [(C+N+O)/Fe] contents. We deal at the same time…

Solar and Stellar Astrophysics · Physics 2016-02-17 Marco Tailo , Marcella Di Criscienzo , Francesca D'Antona , Vittoria Caloi , Paolo Ventura

We explore the metallicity distribution function (MDF) of red giant stars in Omega Centauri from a catalogue of Washington M, T_2 and DDO51 photometry covering over 1.1 deg^2 outside the cluster core. Using updated calibrations of giant…