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Related papers: The Evolution of He4 and LiBeB

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Because of the roughly linear correlation between Be/H and Fe/H in low metallicity halo stars, it has been argued that a ``primary'' component in the nucleosynthesis of Be must be present in addition to the ``secondary'' component from…

Astrophysics · Physics 2009-10-30 Brian D. Fields , Keith A. Olive

We review the Galactic chemical evolution of Li6 and compare these results with recent observational determinations of the lithium isotopic ratio. In particular, we concentrate on so-called standard Galactic cosmic-ray nucleosynthesis in…

Astrophysics · Physics 2009-10-31 Brian D. Fields , Keith A. Olive

We discuss the early evolution of beryllium and oxygen in our Galaxy by comparing abundances of these elements for halo and disk metal-poor stars. Both, O and Be rise as we go progressively to more metal-rich stars, showing a slope 0.41…

Astrophysics · Physics 2007-05-23 Garik Israelian , Ramon Garcia Lopez , Rafael Rebolo

Two aspects of the chemical evolution of 4He in the Galaxy are considered on the basis of a sample of disk planetary nebulae by the application of corrections due to the contamination of 4He from the progenitor stars. First, the He/H radial…

Astrophysics · Physics 2007-05-23 W. J. Maciel

The light elements D, \he3, \he4, and \li7 are produced in big bang nucleosynthesis and undergo changes in their abundances due to galactic processing. Since one may observe most of these elements only in contemporary environments,…

Astrophysics · Physics 2008-11-26 Brian Fields

Big bang nucleosynthesis (BBN) and the cosmic baryon density from cosmic microwave background anisotropies together predict a primordial Li7 abundance a factor of 2--3 higher than that observed in galactic halo dwarf stars. A recent…

Astrophysics · Physics 2008-12-18 Brian D. Fields , Keith A. Olive , Elisabeth Vangioni-Flam

The evolution of the 7Li abundance in the Galaxy has been computed by taking into account several 7Li sources: novae, massive AGB stars, C-stars, Type II SNe and GCRs. The theoretical predictions for the evolution of the 7Li abundance in…

Astrophysics · Physics 2011-05-23 D. Romano , F. Matteucci , P. Molaro , P. Bonifacio

A LiBeB evolution model including Galactic Cosmic Ray nucleosynthesis, the $\nu$-process, novae, AGB and C-stars is presented. We have included Galactic Cosmic Ray Nucleosynthesis (GCRN) in a complete Chemical Evolution Model that takes…

Astrophysics · Physics 2016-11-03 Andreu Alibes , Javier Labay , Ramon Canal

Using a time-dependent Galactic Cosmic Ray flux proportional to the halo Star Formation Rate and including astration and neutrino-induced nucleosynthesis, we have studied the evolution of lithium, beryllium and boron in the halo. Our…

Astrophysics · Physics 2007-05-23 Andreu Alibes , Ramon Canal

Reconstructing the Galactic evolution of lithium (Li) is the main tool used to constrain the source(s) of Li enrichment in the Galaxy. Recent results have suggested a decline in Li at supersolar metallicities, which may indicate reduced…

A highly homogeneous study of 23 halo field dwarf stars has achieved a Li abundance accuracy of 0.033 dex per star. The work shows that the intrinsic spread of the Li abundances of these stars at a given metallicity is <0.02 dex, and…

Astrophysics · Physics 2007-05-23 Sean G. Ryan

We discuss the highlights of our recent research, specifically the refractory vs. volatile interpretation of the rise of [O/Fe] with decreasing [Fe/H], and the issue of primary vs. secondary evolution of Be.

Astrophysics · Physics 2016-11-03 R. Ramaty , R. E. Lingenfelter , B. Kozlovsky

We present predictions of the evolution of the light elements, Li, Be, and B, in the early epochs of the Galactic halo, using a model of supernova-induced chemical evolution based on contributions from supernovae (SNe) and cosmic rays…

Astrophysics · Physics 2009-10-31 Takeru Ken Suzuki , Yuzuru Yoshii

We present extensive calculations of the structure and the evolution of low-massstars in the range 0.07-0.8 $\msol$, for metallicities $-2.0\le \mh \le 0.0$. These calculations are based on the most recent description of the microphysics…

Astrophysics · Physics 2008-11-26 Gilles Chabrier , Isabelle Baraffe

Star formation drives changes in the compositions of galaxies, fusing H and He into heavier nuclei. This paper investigates the differences in abundance evolution between metal and non-metal isotopes using recent models of Galactic chemical…

Astrophysics of Galaxies · Physics 2025-10-13 James W. Johnson , Miqaela K. Weller , Ryan J. Cooke

We calculate the evolution of heavy element abundances from C to Zn in the solar neighborhood adopting our new nucleosynthesis yields. Our yields are calculated for wide ranges of metallicity (Z=0-Z_\odot) and the explosion energy (normal…

Astrophysics · Physics 2008-11-26 C. Kobayashi , H. Umeda , K. Nomoto , N. Tominaga , T. Ohkubo

In order to recognize environmental effects on the evolution of dwarf galaxies in clusters of galaxies, it is first necessary to quantify the properties of objects which have evolved in relative isolation. With oxygen abundance as the gauge…

We investigate the redshift evolution of the [OIII]/Hb nebular emission line ratio for a sample of galaxies spanning the redshift range 0 < z < 4. We compare the observed evolution to a set of theoretical models which account for the…

Astrophysics of Galaxies · Physics 2016-07-27 F. Cullen , M. Cirasuolo , L. J. Kewley , R. J. McLure , J. S. Dunlop , R. A. A. Bowler

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 find that hot jupiter host stars within the T$_\mathrm{eff}$ range 5900-6300K show lower Li abundances, by 0.14 dex, than stars without detected planets. This offset has a significance at the level 7$\sigma$, pointing to a stronger…

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