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Related papers: Galactic Evolution of Beryllium and Oxygen

200 papers

The chemical evolution of the Galactic bulge is treated here in the context of an inside-out model for the Galaxy formation. We assume that this central region evolved even faster than the Galactic halo and test the effect of changing the…

Astrophysics · Physics 2007-05-23 F. Matteucci , D. Romano , P. Molaro

We present observations of the Be II 313.0 nm resonance doublet in 14 halo and old disk stars with metallicities ranging from [Fe/H]=-0.4 to about -3.0 obtained with the CASPEC spectrograph of the ESO 3.6m telescope at a FWHM about 8.6 km/s…

Astrophysics · Physics 2007-05-23 P. Molaro , P. Bonifacio , F. Castelli , L. Pasquini

The early chemical evolution of the Galaxy and the Universe is vital to our understanding of a host of astrophysical phenomena. Since the most metal-poor Galactic stars (with metallicities down to [Fe/H]\sim-5.5) are relics from the…

Astrophysics of Galaxies · Physics 2015-05-30 Anna Frebel

Be abundances of old, low metallicity halo stars have major implications on cosmic-ray origin, requiring acceleration out of fresh supernova ejecta. The observed, essentially constant Be/Fe fixes the Be production per SNII, allowing the…

Astrophysics · Physics 2007-05-23 Reuven Ramaty , Richard Lingenfelter

We explore the hypothesis that the classical and ultra-faint dwarf spheroidal satellites of the Milky Way have been the building blocks of the Galactic halo by comparing their [O/Fe] and [Ba/Fe] versus [Fe/H] patterns with the ones observed…

Astrophysics of Galaxies · Physics 2017-05-19 E. Spitoni , F. Vincenzo , F. Matteucci , D. Romano

The present day chemical and dynamical properties of the Milky Way bear the imprint of the Galaxy's formation and evolutionary history. One of the most enduring and critical debates surrounding Galactic evolution is that regarding the…

Astrophysics · Physics 2009-11-07 Chris B. Brook , Daisuke Kawata , Brad K. Gibson , Chris Flynn

Ground- and space-based observations of stellar heavy element abundances are providing a clearer picture of the chemical evolution of the Galaxy. A large number of (r)apid and (s)low neutron capture process elements, including the first…

Astrophysics · Physics 2007-05-23 John J Cowan , Christopher Sneden , James W Truran , Debra L Burris

We compare abundances patterns in the Bulge for elements observed in stars and in planetary nebulae. Some alpha elements, like Mg and Ti, are overabundant respect to Fe, and others are not, like He, O, Si, S, Ar, Ca. The first ones favor a…

Astrophysics · Physics 2007-05-23 F. Cuisinier , J. Koppen , A. Acker , W. J. Maciel

Recent detailed simulations of Galactic Chemical Evolution have shown that the heavy elements, in particular [Fe/H], are expected to exhibit a weak, or absent, correlation with stellar ages in the early Galaxy due to the lack of efficient…

Astrophysics · Physics 2007-05-23 Timothy C. Beers , Takeru K. Suzuki , Yuzuru Yoshii

Beryllium and oxygen abundances have been derived in a sample of F-type field stars for which lithium abundances had been measured previously, with the aim of obtaining observational constraints to discriminate between the different mixing…

We present a comprehensive study of the evolution of the abundances of intermediate mass elements, from C to Zn, in the Milky Way halo and in the local disk. We use a consistent model to describe the evolution of those two galactic…

Astrophysics · Physics 2007-05-23 Aruna Goswami , Nikos Prantzos

Recent observations demonstrate that the thin and thick disks of the Galaxy have different chemical abundance trends and evolution timescales. The relative abundances of $\alpha$-elements in the thick Galactic disk are increased relative to…

Astrophysics · Physics 2009-11-11 T. V. Nykytyuk , T. V. Mishenina

The origin of the Galactic halo is one of the fundamental topics linking the study of galaxy formation and evolution to cosmology. We aim at deriving precise and accurate stellar parameters, Mg abundances, and ages for a sample of…

Astrophysics of Galaxies · Physics 2025-06-04 Riano E. Giribaldi , Laura Magrini , Martina Rossi , Anish M. Amarsi , Donatella Romano , Davide Massari

From a recent re-analysis of the available data, Be and B Galactic evolution appears to show evidence for a two-slope behaviour with respect to O. The inferred Be/O abundance ratio in halo stars is constant at very low metallicity (primary…

Astrophysics · Physics 2007-05-23 Etienne Parizot

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 a study of beryllium (Be) abundances in a large sample of field solar-type dwarfs and sub-giants spanning a large range of effective temperatures. The analysis shows that Be is severely depleted for F stars, as expected by the…

Astrophysics · Physics 2009-11-10 N. C. Santos , G. Israelian , S. Randich , R. J. Garcia Lopez , R. Rebolo

We have derived beryllium abundances in a wide sample of stars hosting planets, with spectral types in the range F7V-K0V, aimed at studying in detail the effects of the presence of planets on the structure and evolution of the associated…

The chemical composition of stars with extremely low metal contents (taking ``metals'' to mean all elements other than hydrogen and helium) provides us with information on the masses of the stars that produced the first metals. Such a…

Astrophysics · Physics 2015-06-24 Piercarlo Bonifacio , Marco Limongi , Alessandro Chieffi

Two types of models have been proposed to explain the linear rise of the Be and B abundances as a function of iron observed in metal poor halo stars. In both cases, this linearity indicates that freshly synthesized C and O are accelerated…

Astrophysics · Physics 2007-05-23 Elisabeth Vangioni-Flam , Reuven Ramaty , Keith A. Olive , Michel Cassé

We test the hypothesis that the classical and ultra-faint dwarf spheroidal satellites of the our Galaxy have been the building blocks of the Galactic halo by comparing their [O/Fe] and [Ba/Fe] vs. [Fe/H] patterns with the ones observed in…

Astrophysics of Galaxies · Physics 2018-08-22 E. Spitoni , F. Vincenzo , F. Matteucci , D. Romano