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Related papers: Population-Dependent r-process Scatter in the Glob…

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The majority of the inhomogeneities in the chemical composition of Globular Cluster (GC) stars appear due to primordial enrichment by hot-CNO cycled material processed in stars belonging to a first stellar generation. Either massive AGB…

Astrophysics · Physics 2009-11-13 F. D'Antona , V. Caloi

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

We study turbulent gas diffusion affects on $r$-process abundances in Milky Way stars, by a combination of an analytical approach and a Monte Carlo simulation. Higher $r$-process event rates and faster diffusion, lead to more efficient…

High Energy Astrophysical Phenomena · Physics 2020-06-24 Paz Beniamini , Kenta Hotokezaka

Investigations of elemental abundances in the ancient and most metal deficient stars are extremely important because they serve as tests of variable nucleosynthesis pathways and can provide critical inferences of the type of stars that…

We present an empirical s-process abundance distribution derived with explicit knowledge of the r-process component in the low-metallicity globular cluster M22. We have obtained high-resolution, high signal-to-noise spectra for 6 red giants…

Solar and Stellar Astrophysics · Physics 2015-05-30 I. U. Roederer , A. F. Marino , C. Sneden

Although there have been recent claims that there is a large dispersion in the abundances of the heavy neutron capture elements in the old Galactic globular cluster M92, we show that the measured dispersion for the absolute abundances of…

Solar and Stellar Astrophysics · Physics 2015-05-30 Judith G. Cohen

The view of globular clusters (GCs) as simple systems continues to unravel, revealing complex objects hosting multiple chemical peculiarities. Using differential abundance analysis, we probe the chemistry of the Type I GC, NGC 288 and the…

The majority of Galactic globular clusters (GCs) contain multiple stellar populations displaying specific chemical abundance variations. In particular, GCs generally contain a `primordial' population with abundances similar to field stars,…

Astrophysics of Galaxies · Physics 2023-02-01 E. Leitinger , H. Baumgardt , I. Cabrera-Ziri , M. Hilker , E. Pancino

The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters is providing a major breakthrough in our knowledge of Globular Clusters (GCs) and their stellar populations. Among the main results, we discovered that all the…

Context. Thanks to the heroic observational campaigns carried out in recent years we now have large samples of metal-poor stars for which measurements of detailed abundances exist. [...] These data hold important clues on the nature of the…

Astrophysics of Galaxies · Physics 2014-05-08 Gabriele Cescutti , Cristina Chiappini

Recent observations of heavy elements in Globular Clusters reveal intriguing deviations from the standard paradigm of the early galactic nucleosynthesis. If the r-process contamination is a common feature of halo stars, s-process…

Astrophysics of Galaxies · Physics 2015-06-19 Oscar Straniero , Sergio Cristallo , Luciano Piersanti

The formation of populous secondary star cluster systems is a widespread phenomenon in mergers of gas-rich galaxies. Many, if not most, of those clusters are massive and compact enough to be young globular clusters (GCs). GC systems in most…

Astrophysics · Physics 2007-05-23 Uta Fritze-v. Alvensleben , Richard de Grijs

The star-to-star differences in the abundance of light elements observed in the globular clusters (GCs) can be explained assuming that a second generation (SG) of stars form in the gas ejected by the asymptotic giant branch (AGB) stars…

Astrophysics of Galaxies · Physics 2015-05-27 Annibale D'Ercole , Francesca D'Antona , Enrico Vesperini

To better characterize the abundance patterns produced by the r-process, we have derived new abundances or upper limits for the heavy elements zinc (Zn), yttrium (Y), lanthanum (La), europium (Eu), and lead (Pb). Our sample of 161…

Solar and Stellar Astrophysics · Physics 2015-05-20 I. U. Roederer , J. J. Cowan , A. I. Karakas , K. -L. Kratz , M. Lugaro , J. Simmerer , K. Farouqi , C. Sneden

Globular Cluster (GC) formation seems to be a widespread mode of star formation in extreme starbursts triggered by strong interactions and mergers of massive gas-rich galaxies. We use our detailed chemically consistent evolutionary…

Astrophysics · Physics 2015-06-10 Uta Fritze -- v. Alvensleben

Some recent observations of the abundances of s-process, r-process, and alpha elements in metal-poor stars have led to a new scenario for their formation. According to this scenario, these stars were born in a globular cluster and accreted…

Astrophysics · Physics 2009-11-07 A. Thoul , A. Jorissen , S. Goriely , E. Jehin , P. Magain , A. Noels , G. Parmentier

It is now clear that abundance variations from star-to-star among the light elements, particularly C, N, O, Na and Al, are ubiquitous within galactic globular clusters; they appear seen whenever data of high quality is obtained for a…

Astrophysics · Physics 2007-05-23 Judith G. Cohen

We present CN and CH band measurements for 137 RGB and AGB stars in the Galactic globular cluster M10. Our measurements come from low resolution spectroscopy taken with the Hydra spectrograph on the WIYN-3.5m telescope. We use these…

Solar and Stellar Astrophysics · Physics 2018-06-12 Jeffrey M. Gerber , Eileen D. Friel , Enrico Vesperini

Atomic diffusion in stars can create systematic trends of surface abundances with evolutionary stage. Globular clusters offer useful laboratories to put observational constraints on this theory as one needs to compare abundances in…

The degree of influence that environment and mass have on the stellar populations of early-type galaxies is uncertain. In this paper we present the results of a spectroscopic analysis of the stellar populations of early-type galaxies aimed…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Craig Harrison , Matthew Colless , Harald Kuntschner , Warrick Couch , Roberto De Propris , Michael Pracy