A New Model for the Evolution of Light Elements in an Inhomogeneous Galactic Halo

Abstract

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 (CRs). The most important prediction from our model is that the abundances of light elements in extremely metal-poor stars might be used as age indicators in the very early stages of an evolving halo population, at times when metallicity in most stars are dominated by local metal enrichment due to nearby SN events, and is poorly correlated with age. Our results show that the best ``cosmic clock'' is the ${}^6$Li abundance. We have derived relationships among various cosmic-ray parameters. Although our model is successful for certain sets of cosmic-ray parameters, larger energy should be absorbed by energetic particles from each SN than required to the current situation of Galactic disk. We discuss an alternative hypothesis of AGN activity in the early Galaxy as another possible accelerator of CRs.

ApJ in press, 32 pages including 8 figures (3 fiures, fig.3,5,& 7 in color)

References in corpus (8)

• Presupernova Evolution of Rotating Massive Stars I: Numerical Method and Evolution of the Internal Stellar Structure
• Kinematics of Metal-Poor Stars in the Galaxy. III. Formation of the Stellar Halo and Thick Disk as Revealed from a Large Sample of Non-Kinematically Selected Stars
• Chemical Evolution of the Galactic Halo through Supernova-Induced Star Formation and Its Implication for Population III Stars
• Light Element Evolution and Cosmic Ray Energetics
• Testing Spallation Processes With Beryllium and Boron
• Evolution of Beryllium and Boron in the Inhomogeneous Early Galaxy
• Primordial Lithium Abundance as a Stringent Constraint on the Baryonic Content of the Universe
• An Application of Kerr Blackhole Fly-Wheel Model to Statistical Properties of QSOs/AGNs

Cited by in corpus (28)

• Lithium isotopic abundances in metal-poor halo stars
• 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
• Galactic Chemical Evolution
• Cosmic Ray Production of Lithium-6 by Structure Formation Shocks in the Early Milky Way: A Fossil Record of Dissipative Processes during Galaxy Formation
• Beryllium in turnoff stars of NGC6397: early Galaxy spallation, cosmochronology and cluster formation
• Beryllium abundances in metal-poor stars
• Beryllium, Oxygen and Iron Abundances in Extremely Metal-Deficient Stars
• Light Elements in the Universe
• Possible signature of hypernova nucleosynthesis in a beryllium rich halo dwarf
• Beryllium abundance in turn-off stars of NGC 6752
• Roles of Supernova Ejecta in Nucleosynthesis of Light Elements, Li, Be, and B
• Early star formation in the Galaxy from beryllium and oxygen abundances
• A low upper-limit on the lithium isotope ratio in HD140283
• Pregalactic LiBeB Production by Supernova Cosmic Rays
• Light Element Production in the Circumstellar Matter of Energetic Type Ic Supernovae
• A possible signature of non-uniform Be-αrelationships for the Galaxy
• Be and O in the ultra metal-poor dwarf 2MASS J18082002-5104378: The Be-O correlation
• Inhomogeneity in the early Galactic chemical enrichment exposed by beryllium abundances in extremely metal-poor stars
• Sandblasting the $\text{r}$-Process: Spallation of Ejecta from Neutron Star Mergers
• Stellar abundances of beryllium and CUBES
• Detecting weak beryllium lines with CUBES
• Cosmic Ray Production of ${}^6$Li by Structure Formation Shocks in the Early Galaxy
• A view of the Galactic halo using beryllium as a time scale
• Modelling the chemical evolution of the Milky Way
• The CUBES Science Case
• Spallation of r-Process Nuclei Ejected from a Neutron Star Merger
• Beryllium abundances and the formation of the halo and the thick disk