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Related papers: LiBeB Evolution: Three Models

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Three different models have been proposed for LiBeB production by cosmic rays: the CRI model in which the cosmic rays are accelerated out of an ISM of solar composition scaled with metallicity; the CRS model in which cosmic rays with…

Astrophysics · Physics 2009-10-31 Reuven Ramaty , Richard Lingenfelter

Using cosmic-ray energetics as a discriminator, we investigate evolutionary models of LiBeB. We employ a Monte Carlo code which incorporates the delayed mixing into the ISM both of the synthesized Fe, due to its incorporation into high…

Astrophysics · Physics 2009-10-31 R. Ramaty , S. T. Scully , R. E. Lingenfelter , B. Kozlovsky

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

Be abundances at low metallicities 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 determination of…

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

In this article we study the galactic evolution of the LiBeB elements within the framework of a detailed model of the chemical evolution of the Galaxy that includes galactic cosmic ray nucleosynthesis by particles accelerated in…

Astrophysics · Physics 2009-11-07 Andreu Alibes , Javier Labay , Ramon Canal

We reassess the problem of the production and evolution of the light elements Li, Be and B and of their isotopes in the Milky Way, in the light of new observational and theoretical developments. The main novelty is the introduction of a new…

Astrophysics of Galaxies · Physics 2015-06-04 N. Prantzos

Employing a Monte-Carlo based evolutionary code, we show that the delay of Fe deposition relative to O, due to the incorporation of supernova ejecta refractories in high velocity grains, can account for the rise of [O/Fe] with decreasing…

Astrophysics · Physics 2007-05-23 R. Ramaty , B. Kozlovsky , R. E. Lingenfelter

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

Oxygen is a much better evolutionary index than iron to describe the history of Lithium-Beryllium-Boron (LiBeB) since it is the main producer of these light elements at least in the early Galaxy. The O-Fe relation is crucial to the…

Astrophysics · Physics 2009-11-06 Elisabeth Vangioni-Flam , Michel Casse

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

Using a Monte Carlo code which incorporates the delayed mixing into the ISM of supernovae nucleosynthetic yields and ejecta kinetic energies (including events with very large energies, e.g. collapsars/hypernovae), we tested three…

Astrophysics · Physics 2007-05-23 R. Ramaty , R. E. Lingenfelter

The galactic chemical evolution of Be and B provides unique information about the origin and history of cosmic rays. The available Pop II data demonstrate that Be and B have a Galactic source, probably in one or more kinds of spallation…

Astrophysics · Physics 2007-05-23 Brian D. Fields , Keith A. Olive

It is well known that no time-independent galactic cosmic ray (GCR) flux model can account for the observed linear relationship of Be and B abundances with metallicity. In this contribution we solve the time-dependent CR propagation…

Astrophysics · Physics 2007-05-23 Carlos Abia , Ute Lisenfeld , Jordi Isern

To understand better the early galactic production of Li, Be, and B by cosmic ray spallation and fusion reactions, the dependence of these production rates on cosmic ray models and model parameters is examined. The sensitivity of elemental…

Astrophysics · Physics 2009-09-25 Brian Fields , Keith Olive , David Schramm

Using recent measurements of the spectrum and chemical composition of the highest energy cosmic rays, we consider the sources of these particles. We find that the data strongly prefers models in which the sources of the ultra-high energy…

High Energy Astrophysical Phenomena · Physics 2015-09-23 Andrew M. Taylor , Markus Ahlers , Dan Hooper

The production of LiBeB isotopes by nuclear and neutrino spallation are compared in the framework of galactic evolutionary models. As motivated by $\gamma$-ray observations of Orion, different possible sources of low-energy C and O nuclei…

Astrophysics · Physics 2009-09-15 Elisabeth Vangioni-Flam , Michel Cassé , Brian D. Fields , Keith A. Olive

The recent observations of Be and B in metal poor stars has led to a reassessment of the origin of the light elements in the early Galaxy. At low it is metallicity ([O/H] < -1.75), it is necessary to introduce a production mechanism which…

Astrophysics · Physics 2009-09-15 Brian D. Fields , Keith A. Olive , Michel Casse , Elisabeth Vangioni-Flam

A short overview is presented of current issues concerning the production and evolution of Li, Be and B in the Milky Way. In particular, the observed "primary-like" evolution of Be is re-assessed in the light of a novel idea: it is argued…

Astrophysics of Galaxies · Physics 2015-05-18 Nikos Prantzos

Our understanding of the evolution of He4 and Li7 depends critically on the available data for these two elements at low metallicity. In particular, the degree to which there is a slope in an abundance vs metallicity regression can help…

Astrophysics · Physics 2007-05-23 Keith A. Olive

Oxygen is a much better evolutionary index than iron to follow the history of Lithium-Beryllium-Boron (LiBeB) since it is the main producer of these light elements at least in the early Galaxy. The O-Fe relation is crucial to the…

Astrophysics · Physics 2007-05-23 Elisabeth Vangioni-Flam , Michel Casse
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