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Related papers: The Mg-K anti-correlation in Omega Centauri

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Having shown in a recent paper that the main sequence of omega Centauri is split into two distinct branches, we now present spectroscopic results showing that the bluer sequence is_less_ metal-poor. We have carefully combined GIRAFFE@VLT…

UV observations of some massive globular clusters have revealed a significant population of stars hotter and fainter than the hot end of the horizontal branch (HB), the so-called blue hook stars. This feature might be explained either by…

Solar and Stellar Astrophysics · Physics 2015-05-20 S. Moehler , S. Dreizler , T. Lanz , G. Bono , A. V. Sweigart , A. Calamida , M. Nonino

We present radial velocities and chemical abundances of O, Na, Mg, Al, Si, Ca, Cr, Fe, Co, Ni, and Cu for a sample of 156 red giant branch stars in two Galactic bulge fields centered near (l,b)=(+5.25,-3.02) and (0,-12). The (+5.25,-3.02)…

Solar and Stellar Astrophysics · Physics 2015-06-22 Christian I. Johnson , R. Michael Rich , Chiaki Kobayashi , Andrea Kunder , Andreas Koch

We present aluminium, magnesium, and silicon abundances in the metal-poor globular cluster NGC 6752 for a sample of more than 130 red giants with homogeneous oxygen and sodium abundances. We find that [Al/Fe] shows a spread of about 1.4 dex…

Astrophysics of Galaxies · Physics 2015-06-04 Eugenio Carretta , Angela Bragaglia , Raffaele Gratton , Sara Lucatello , Valentina D'Orazi

Sulphur is an important, volatile alpha element but its role in the Galactic chemical evolution is still uncertain. We derive the S abundances in RGB stars in three Galactic globular clusters (GC) that cover a wide metallicity range…

Astrophysics of Galaxies · Physics 2015-04-29 Nikolay Kacharov , Andreas Koch , Elisabetta Caffau , Luca Sbordone

We present a near-infrared J and K photometric catalog containing more than 73,000 stars in the central region of the giant Globular Cluster omega Centauri. This is the largest IR data-set ever published for this cluster and has been used…

Astrophysics · Physics 2009-11-10 A. Sollima , F. R. Ferraro , L. Origlia , E. Pancino , M. Bellazzini

We present a chemical composition analysis of 36 giant stars in mildly metal-poor globular cluster M5. In comparing the M5 results to those obtained in M4, a cluster previously considered to be a ``twin'' in age, metallicity and chemical…

We present spectral energy distribution modelling of 6875 stars in omega Centauri, obtaining stellar luminosities and temperatures by fitting literature photometry to state-of-the-art MARCS stellar models. By comparison to four different…

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…

We present abundances of globular clusters in the Milky Way and Fornax from integrated light spectra. Our goal is to evaluate the consistency of the integrated light analysis relative to standard abundance analysis for individual stars in…

Astrophysics of Galaxies · Physics 2017-01-11 J. E. Colucci , R. A. Bernstein , A. McWilliam

The accurate O, Mg and Fe abundances derived in previous papers of this series from a homogenous reanalysis of high quality data for a large sample of stars are combined with stellar kinematics in order to discuss the history of star…

Astrophysics · Physics 2007-05-23 Raffaele Gratton , Eugenio Carretta , Francesca Matteucci , Chris Sneden

We present new Near-Infrared (J,K) magnitudes for 114 RR Lyrae stars in the globular cluster Omega Cen (NGC 5139) which we combine with data from the literature to construct a sample of 180 RR Lyrae stars with J and K mean magnitudes on a…

We report on detailed abundances of giants in the Galactic bulge, measured with the HIRES echelle spectrograph on the 10-m Keck telescope. We also review other work on the bulge field population and globular clusters using Keck/HIRES. Our…

Astrophysics · Physics 2015-06-24 R. M. Rich , A. McWilliam

We have analyzed high-resolution and high signal-to-noise ratio optical spectra of nearby FGK stars with and without detected giant planets in order to homogeneously measure their photospheric parameters, mass, age, and the abundances of…

Solar and Stellar Astrophysics · Physics 2015-07-29 R. da Silva , A. C. Milone , H. J. Rocha-Pinto

We investigate a peculiar feature at the hottest, blue end of the horizontal branch of Galactic globular cluster omega Centauri, using the high-precision and nearly complete catalog that has been constructed from a survey taken with the ACS…

Solar and Stellar Astrophysics · Physics 2015-05-13 S. Cassisi , M. Salaris , J. Anderson , G. Piotto , A. Pietrinferni , A. Milone , A. Bellini , R. L. Bedin

We measure chemical abundances for over 20 elements of 15 N-rich field stars with high resolution ($R \sim 30000$) optical spectra. We find that Na, Mg, Al, Si, and Ca abundances of our N-rich field stars are mostly consistent with those of…

Astrophysics of Galaxies · Physics 2021-06-02 Jincheng Yu , Baitian Tang , J. G. Fernandez-Trincado , Douglas Geisler , Hongliang Yan , M. Soto

The peculiar Galactic globular cluster $\omega$ Centauri (NGC 5139) has drawn attention for its unique features - such as a high stellar mass and a broad distribution of chemical elements - that have led to the hypothesis that it might be…

By using the multifiber spectrograph FLAMES mounted at the ESO-VLT, we have obtained high-resolution spectra for 18 giant stars, belonging to 3 old globular clusters of the Large Magellanic Cloud (namely NGC 1786, 2210 and 2257). While…

Solar and Stellar Astrophysics · Physics 2009-11-13 A. Mucciarelli , L. Origlia , F. R. Ferraro , E. Pancino

Understanding the chemical enrichment of different elements is crucial to gaining a complete picture of galaxy chemical evolution. In this study, we present a new sample of 46 low-redshift, low-mass star-forming galaxies at $M_*\sim…

We present the analysis of an extensive set of new and literature high quality data concerning Fe, C, N, O, Na, and Mg, exploiting the Teff scale determined in Gratton et al. (1996), and the non-LTE abundance corrections computed in Gratton…

Astrophysics · Physics 2007-05-23 Eugenio Carretta , Raffaele Gratton , Chris Sneden
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