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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

Solar flare observations are used to demonstrate the new technique of abundance determination based on gamma ray line emission produced by accelerated particle bombardment. Some of the implications of similar gamma ray line emission…

Astrophysics · Physics 2007-05-23 Reuven Ramaty

We derive constraints on the cosmic rays responsible for the Be and part of the B observed in stars formed in the early Galaxy: the cosmic rays cannot be accelerated from the ISM; their energy spectrum must be relatively hard (the bulk of…

Astrophysics · Physics 2009-10-28 R. Ramaty , B. Kozlovsky , R. E. Lingenfelter

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

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

A short overview is presented of current issues concerning the production and evolution of Li, Be and B in the Milky Way. It is argued that the currently popular idea that Galactic cosmic rays are accelerated inside metal-rich superbubbles…

Astrophysics · Physics 2007-05-23 Nikos Prantzos

The ratio of the fluxes of secondary and primary nuclei in cosmic rays has long been used as an indicator of the grammage traversed in the journey of cosmic ray particles throughout the Galaxy. The basic idea is that primary particles are…

High Energy Astrophysical Phenomena · Physics 2017-08-09 Pasquale Blasi

We take a phenomenological approach in a minimal model to understand the spectral intensity of secondary cosmic-ray particles like positrons, antiprotons, Lithium, Beryllium and Boron. Our analysis shows that cosmic rays at $\sim$ GeV…

High Energy Astrophysical Phenomena · Physics 2023-09-13 Ramanath Cowsik , Dawson Huth

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

We consider the production of $^6$Li in spallation reactions by cosmic rays in order to explain the observed abundance in halo metal-poor stars. We show that heating of ambient gas by cosmic rays is an inevitable consequence of this…

Astrophysics · Physics 2009-11-13 Biman B. Nath , Piero Madau , Joseph Silk

Recently, new observations of Li6 in Pop II stars of the galactic halo have shown a surprisingly high abundance of this isotope, about a thousand times higher than its predicted primordial value. In previous papers, a cosmological model for…

Astrophysics · Physics 2009-01-15 Emmanuel Rollinde , David Maurin , Elisabeth Vangioni , Keith A. Olive , Susumu Inoue

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

The energy output (per logarithmic interval of particle energies) of Cosmic Rays (CRs) with energies $10{\rm GeV}\lesssim\varepsilon_p\lesssim100{\rm GeV}$ is $\sim 10^{47}\rm erg$ per solar mass of star$-$formation, based on the CR…

High Energy Astrophysical Phenomena · Physics 2013-11-05 Boaz Katz , Eli Waxman , Todd Thompson , Abraham Loeb

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

The energy dissipated by virialization shocks during hierarchical structure formation of the Galaxy can exceed that injected by concomitant supernova (SN) explosions. Cosmic rays (CRs) accelerated by such shocks may therefore dominate over…

Astrophysics · Physics 2007-05-23 Takeru K. Suzuki , Susumu Inoue

The production of energetic particles in the universe remains one of the great mysteries of modern science. The mechanisms of acceleration in astrophysical sources and the details about the propagation through the galactic and extragalactic…

High Energy Astrophysical Phenomena · Physics 2015-08-06 C. J. Todero Peixoto , Vitor de Souza , Peter L. Biermann

I calculate the evolution of Be and B abundances produced by cosmic rays generated by massive stars in the pregalactic phase of the universe. The inputs for calculation, i.e. the star formation rate and the nuclear abundances of cosmic…

Astrophysics · Physics 2013-03-21 Motohiko Kusakabe

While the abundances of Be and B observed in metal-poor halo stars are well explained as resulting from spallation of CNO-enriched cosmic rays (CRs) accelerated by supernova shocks, accounting for the observed $^6$Li in such stars with…

Astrophysics · Physics 2009-11-07 Takeru K. Suzuki , Susumu Inoue

Galactic cosmic-ray source compositions, (Z/H)GCRS from H to Pb and ~10^8 - 10^14 eV, differ from solar-local interstellar, (Z/H)SS or (Z/H)ISM by ~20-200x. Both are mostly just mixes of core collapse (CCSN) and thermonuclear (SN Ia)…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Richard E. Lingenfelter

The composition of present day cosmic rays (CRs) is inconsistent with a significant acceleration of SN ejecta material (even with a preferential acceleration of ejecta grain material). Current CRs must result mainly from the acceleration of…

Astrophysics · Physics 2007-05-23 J. P. Meyer , D. C. Ellison
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