Production of 9Be through alpha-fusion reaction of metal-poor cosmic ray and stellar flare
arXiv:1208.4210 · doi:10.1088/0004-637X/767/1/5
Abstract
Spectroscopic observations of metal-poor stars have indicated possible 6Li abundances that are much larger than the primordial abundance predicted in the standard big bang nucleosynthesis model. Possible mechanisms of 6Li production in metal-poor stars include pregalactic and cosmological cosmic ray (CR) nucleosynthesis and nucleosynthesis by flare-accelerated nuclides. We study 9Be production via two-step alpha-fusion reactions of CR or flare-accelerated 3,4He through 6He and 6,7Li, in pregalactic structure, intergalactic medium, and stellar surfaces. We solve transfer equations of CR or flare particles and calculate nuclear yields of 6He, 6,7Li, and 9Be taking account of probabilities of processing 6He and 6,7Li into 9Be via fusions with alpha particles. Yield ratios, i.e., 9Be/6Li, are then calculated for the CR and flare nucleosynthesis models. We suggest that the future observations of 9Be in metal-poor stars may find enhanced abundances originating from metal-poor CR or flare activities.
arXiv comment28 pages, 9 figures, argument and new Fig. 5 added in section 4, minor modifications added, results slightly changed only quantitatively, minor modifications added again
References in corpus (29)
- Lithium isotopic abundances in metal-poor halo stars
- Standard Big-Bang Nucleosynthesis up to CNO with an improved extended nuclear network
- Production and evolution of Li, Be and B isotopes in the Galaxy
- Light Elements and Cosmic Rays in the Early Galaxy
- Line shift, line asymmetry, and the 6Li/7Li isotopic ratio determination
- BD +44 493: A Ninth Magnitude Messenger from the Early Universe; Carbon Enhanced and Beryllium Poor
- Beryllium abundances and star formation in the halo and in the thick disk
- Beryllium and Alpha-Element Abundances in a Large Sample of Metal-Poor Stars
- Cosmic Ray Production of Lithium-6 by Structure Formation Shocks in the Early Milky Way: A Fossil Record of Dissipative Processes during Galaxy Formation
- Hierarchical Growth and Cosmic Star Formation: Enrichment, Outflows and Supernova Rates
- Boron in Very Metal-Poor Stars
- Cosmological Cosmic Rays and the observed Li6 plateau in metal poor halo stars
- Testing Spallation Processes With Beryllium and Boron
- Evolution of Li, Be and B in the Galaxy
- Beryllium abundances in metal-poor stars
- Population III Generated Cosmic Rays and the Production of Li6
- Beryllium, Oxygen and Iron Abundances in Extremely Metal-Deficient Stars
- Beryllium in Disk and Halo Stars -- Evidence for a Beryllium Dispersion in Old Stars
- 6Li/7Li estimates for metal-poor stars
- Production of Lithium, Beryllium, and Boron by Hypernovae
- Is 6-Li in metal-poor halo stars produced in situ by solar-like flares?
- The energetics, evolution, and stellar depletion of Li6 in the early Galaxy
- Lithium-6 from Solar Flares
- Cosmic Ray production of Beryllium and Boron at high redshift
- Roles of Supernova Ejecta in Nucleosynthesis of Light Elements, Li, Be, and B
- Light Element Production in the Circumstellar Matter of Energetic Type Ic Supernovae
- Pregalactic LiBeB Production by Supernova Cosmic Rays
- Nuclear and Gamma-ray Production by Supernova Ejecta
- The puzzling origin of the 6Li plateau