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Related papers: Heavy elements and chemical enrichment in globular…

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High resolution spectra (R > 40 000) for 9 main sequence turn-off stars and 9 subgiants in the globular cluster NGC 6752 were acquired with UVES on the VLT-Kueyen (UT2). These data have been used to determine the abundances of some heavy…

The [Sr/Ba] and [Y/Ba] scatter observed in some galactic halo stars that are very metal-poor stars and in a few individual stars of the oldest known Milky Way globular cluster NGC 6522,have been interpreted as evidence of early enrichment…

Solar and Stellar Astrophysics · Physics 2015-06-22 B. Barbuy , C. Chiappini , E. Cantelli , E. Depagne , M. Pignatari , R. Hirschi , G. Cescutti , S. Ortolani , V. Hill , M. Zoccali , D. Minniti , M. Trevisan , E. Bica , A. Gómez

The properties of the relative abundances of rapid and slow neutron-capture elements are studied using a catalog containing spectroscopic abundance determinations for 14~elements produced in various nuclear-synthesis processes for 90~open…

Astrophysics of Galaxies · Physics 2016-02-22 V. A. Marsakov , M. L. Gozha , V. V. Koval' , L. V. Shpigel'

Globular clusters (GCs) are key to understanding the formation and evolution of our Galaxy. While the abundances of light and Fe-peak elements in GCs have been widely studied, investigations into heavier, neutron-capture elements -- and…

The globular cluster HP~1 is projected at only 3.33 degrees from the Galactic center. Together with its distance, this makes it one of the most central globular clusters in the Milky Way. It has a blue horizontal branch (BHB) and a…

Solar and Stellar Astrophysics · Physics 2016-06-22 B. Barbuy , E. Cantelli , A. Vemado , H. Ernandes , S. Ortolani , I. Saviane , E. Bica , D. Minniti , B. Dias , Y. Momany , V. Hill , M. Zoccali , C. Siqueira-Mello

Context. Globular clusters are considered key objects for understanding the formation and evolution of the Milky Way. In this sense, their characterisation in terms of their chemical and orbital parameters can provide constraints to the…

Astrophysics of Galaxies · Physics 2024-02-12 J. Schiappacasse-Ulloa , S. Lucatello , G. Cescutti , E. Carretta

Context: Globular clusters (GCs) in the outer halo are important probes of the composition and origin of the Galactic stellar halo. Aims: We derive chemical element abundance ratios in red giants belonging to the remote (R~90 kpc) GC Pal 3…

Astrophysics of Galaxies · Physics 2015-05-13 Andreas Koch , Patrick Côté , Andrew McWilliam

We present the results of the analysis of high-resolution spectra obtained with UVES-FLAMES@VLT for six red giant branch stars in the outer-halo metal-poor ([Fe/H]I=-1.98 and [Fe/H]II=-1.83) Galactic globular cluster NGC 5694, which has…

Solar and Stellar Astrophysics · Physics 2015-06-17 A. Mucciarelli , M. Bellazzini , M. Catelan , E. Dalessandro , P. Amigo , M. Correnti , C. Cortés , V. D'Orazi

The aim of this work is to measure the abundances of n-capture elements in a sample of six metal-poor N-rich dwarfs that were formed in globular clusters, and subsequently became unbound from the cluster. These N-rich stars, HD 25329, HD…

Solar and Stellar Astrophysics · Physics 2024-04-18 M Spite , P Bonifacio , E Caffau , P François

We have observed 15 red giant stars in the relatively massive, metal-poor globular cluster NGC 4833 using the Magellan Inamori Kyocera Echelle spectrograph at Magellan. We calculate stellar parameters for each star and perform a standard…

Solar and Stellar Astrophysics · Physics 2015-06-24 Ian U. Roederer , Ian B. Thompson

New elemental abundances for the neutron-capture elements Sr, Nb, Mo, Ru, La, Sm, and Eu are presented for a large sample of 180 barium (Ba) giant stars, a class of chemically peculiar objects that exhibit in their spectra enhancements of…

Solar and Stellar Astrophysics · Physics 2021-08-19 M. P. Roriz , M. Lugaro , C. B. Pereira , C. Sneden , S. Junqueira , A. I. Karakas , N. A. Drake

Although globular clusters are generally chemically homogeneous, substantial abundance variations are sometimes seen even among unevolved main sequence stars, especially for the CNO group of elements. Multi-object intermediate-dispersion…

Astrophysics · Physics 2007-05-23 Russell Cannon , Gary Da Costa , John Norris , Laura Stanford , Barry Croke

We present the first comprehensive abundance study of the massive, outer halo globular cluster (GC) M 75 (NGC 6864). This unique system shows a very extended trimodal horizontal branch (HB), but no other clues for multiple populations have…

Astrophysics of Galaxies · Physics 2013-01-11 Nikolay Kacharov , Andreas Koch

We present a comprehensive abundance analysis of 27 heavy elements in bright giant stars of the globular clusters M4 and M5 based on high resolution, high signal-to-noise ratio spectra obtained with the Magellan Clay Telescope. We confirm…

We have determined Al, $\alpha$, Fe-peak, and neutron capture elemental abundances for five red giant branch (RGB) stars in the Galactic globular cluster M10. Abundances were determined using equivalent width analyses of moderate resolution…

We present a detailed chemical composition analysis of 35 red giant stars in the globular cluster M22. High resolution spectra for this study were obtained at five observatories, and analyzed in a uniform manner. We have determined…

Globular clusters are tracers of the history of star formation and chemical enrichment in the early Galaxy. Their abundance pattern can help understanding their chemical enrichment processes. In particular, the iron-peak elements have been…

Solar and Stellar Astrophysics · Physics 2018-08-08 H. Ernandes , B. Barbuy , A. Alves-Brito , A. Friaca , C. Siqueira-Mello , D. M. Allen

Abundances of about 18 elements including the heavy elements Y and Zr are determined from Hubble Space Telescope Space Telescope Imaging Spectrograph ultraviolet spectra of seven extreme helium stars (EHes): LSE 78, BD+10 2179, V1920 Cyg,…

Astrophysics · Physics 2016-08-30 Gajendra Pandey , David L. Lambert , C. Simon Jeffery , N. Kameswara Rao

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 use abundances of Ca, O, Na, Al from high resolution UVES spectra of 200 red giants in 17 globular clusters (GCs) to investigate the correlation found by Lee et al. (2009) between chemical enrichment from SN II and star-to-star…

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