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Related papers: Magnesium Isotope Ratios in omega Centauri Red Gia…

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We perform a detailed spatially-resolved, spectroscopic, analysis of the core of the Centaurus cluster of galaxies using a deep Chandra X-ray observation and XMM-Newton data. The Centaurus cluster core has particularly high metallicity,…

Astrophysics · Physics 2009-09-17 J. S. Sanders , A. C. Fabian

The globular cluster $\omega$ Centauri (NGC 5139) is a puzzling stellar system harboring several distinct stellar populations whose origin still represents a unique astrophysical challenge. Current scenarios range from primordial chemical…

Astrophysics of Galaxies · Physics 2014-11-20 Sandro Villanova , Giovanni Carraro , Riccardo Scarpa , Gianni Marconi

We present new spectroscopic metal abundances for 74 RR Lyrae stars in omega Cen obtained with FLAMES. The well-known metallicity spread is visible among the RR Lyrae variables. The metal-intermediate (MInt) RR Lyrae stars ([Fe/H] ~ -1.2)…

Astrophysics · Physics 2009-11-11 A. Sollima , J. Borissova , M. Catelan , H. A. Smith , D. Minniti , C. Cacciari , F. R. Ferraro

Recent wide-field photometric surveys (Lee et al.; Pancino et al.) have shown the existence of a previously unknown metal-rich ([Fe/H] -0.6) stellar population in the galactic globular cluster omega Centauri. The discovery of this new…

Astrophysics · Physics 2009-11-07 F. R. Ferraro , M. Bellazzini , E. Pancino

We have determined stellar parameters and abundances for 221 giant branch stars in the globular cluster {\omega} Centauri. A combination of photometry and lower-resolution spectroscopy was used to determine temperature, gravity,…

Solar and Stellar Astrophysics · Physics 2015-06-11 Jeffrey D. Simpson , P. L. Cottrell , C. C. Worley

We present metallicity measurements based on GIRAFFE@VLT spectra of 80 subgiant-branch stars of the Galactic globular cluster Omega Centauri. The VLT spectroscopic data are complemented by ACS/HST and [email protected] high-accuracy…

High-resolution (R ~ 100 000), high signal-to-noise spectra of M71 giants have been obtained with HIRES at the KeckI Telescope in order to measure their Mg isotopic ratios, as well as elemental abundances of C, N, O, Na, Mg, Al, Si, Ca, Ti,…

Astrophysics of Galaxies · Physics 2015-05-13 Jorge Melendez , Judy Cohen

We report new chemical abundances of 23 bright red giants of the globular cluster M3, based on high-resolution spectra obtained with the Keck I telescope. Combining these data with a previously-reported small sample of M3 giants obtained…

In this contribution, results from CCD vby Stroemgren photometry of a statistically complete sample of red giants and stars in the main sequence turn-off region in omega Centauri are presented. From the location of stars in the (b-y),m_1…

Astrophysics · Physics 2007-05-23 Michael Hilker , Tom Richtler

We have observed ten red giant stars in four old Large Magellanic Cloud globular clusters with the high-resolution spectrograph MIKE on the Magellan Landon Clay 6.5-m telescope. The stars in our sample have up to 20 elemental abundance…

Astrophysics · Physics 2009-11-13 Jennifer A. Johnson , Inese I. Ivans , Peter B. Stetson

Globular Clusters (GCs) are natural laboratories where stellar and chemical evolution can be studied in detail. In addition, their chemical patterns and kinematics can tell us wich Galactic structure (Disk, Bulge, Halo or extragalactic) the…

Solar and Stellar Astrophysics · Physics 2018-01-10 A. Mura-Guzmán , S. Villanova , C. Muñoz , B. Tang

Two independent studies recently uncovered two distinct populations among giants in the distant, massive globular cluster (GC) NGC 2419. One of these populations has normal magnesium (Mg) and potassium (K) abundances for halo stars:…

We present a multiple stellar population study of the metal-poor globular cluster (GC) M92 (NGC 6341), which is long known for the substantial metallicity dispersion, using our own photometric system. We find two groups with slightly…

Astrophysics of Galaxies · Physics 2023-05-17 Jae-Woo Lee

Chemical abundances of about fifteen elements from oxygen to europium are measured in seven red giants of the two open clusters NGC 2360 and NGC 2447. The effective temperatures of the giants are determined spectroscopically by taking…

Astrophysics · Physics 2007-05-23 S. Hamdani , P. North , N. Mowlavi , D. Raboud , J. -C. Mermilliod

We report the discovery of two Li-rich giant stars (fainter than the red giant branch bump) in the stellar system Omega Centauri using GIRAFFE-FLAMES spectra. These two stars have A(Li)=1.65 and 2.40 dex and they belong to the main…

Solar and Stellar Astrophysics · Physics 2019-03-13 A. Mucciarelli , L. Monaco , P. Bonifacio , M. Salaris , X. Fu , S. Villanova

We present a chemical composition analysis of 36 giant stars in the mildly metal-poor globular cluster M5 (NGC 5904). The analysis makes use of high resolution data acquired at the Keck I telescope as well as a re-analysis of high…

The abundances of O, Mg, Si and Fe in the intracluster medium of the Centaurus cluster are derived. The Fe abundance has a negative radial gradient. In solar units, the Si abundance is close to the Fe abundance, while the O and Mg…

Astrophysics · Physics 2009-11-11 Kyoko Matsushita , Hans Boehringer , Isao Takahashi , Yasushi Ikebe

Our FLAMES survey of Na-O anticorrelation in globular clusters (GCs) is extended to NGC 4833, a metal-poor GC with a long blue tail on the horizontal branch (HB). We present the abundance analysis for a large sample of 78 red giants based…

Astrophysics of Galaxies · Physics 2015-06-18 E. Carretta , A. Bragaglia , R. G. Gratton , V. D'Orazi , S. Lucatello , Y. Momany , A. Sollima , M. Bellazzini , G. Catanzaro , F. Leone

Omega Centauri ($\omega$ Cen) is the most massive globular cluster of the Milky Way and has been the focus of many studies that reveal the complexity of its stellar populations and kinematics. However, most previous studies have used…

We present age estimates for over 8100 sub-giant branch (SGB) stars in Omega Centauri ($\omega$ Cen) to study its star formation history. Our large data set, which combines multi-wavelength HST photometry with MUSE metallicities, provides…