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Cosmic ray models for early galactic lithium, beryllium, and boron production
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Fields, Brian D. Schramm, David N. Olive, Keith A. |
| Copyright Year | 1994 |
| Description | To better understand 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 and isotropic production to the cosmic ray pathlength magnitude and energy dependence, source spectrum spallation kinematics, and cross section uncertainties is studied. Changes in these model features, particularly those features related to confinement, are shown to alter the Be- and B-versus-Fe slopes from a naive quadratic relation. The implications of our results for the diffuse gamma-ray background are examined, and the role of chemical evolution and its relation to our results is noted. It is also noted that the unmeasured high energy behavior of alpha + alpha fusion can lead to effects as large as a factor of 2 in the resultant yields. Future data should enable Population II Li, Be, and B abundances to constrain cosmic ray models for the early Galaxy. |
| File Size | 2645435 |
| Page Count | 58 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19950012550 |
| Archival Resource Key | ark:/13960/t8tb61v94 |
| Language | English |
| Publisher Date | 1994-01-01 |
| Access Restriction | Open |
| Subject Keyword | Nuclear And High-energy Physics Galactic Evolution Abundance Lithium Cosmic Rays Gamma Rays Isotropy Boron Stellar Composition Nuclear Fusion Computational Astrophysics Spectrum Analysis Astronomical Models Beryllium Kinematics Spallation Chemical Evolution Background Radiation Ntrs Nasa Technical Reports ServerĀ (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |