TY - JOUR
T1 - Cosmic-ray models for early Galactic lithium, beryllium, and boron production
AU - Fields, Brian D.
AU - Olive, Keith A.
AU - Schramm, David N.
PY - 1994/11/1
Y1 - 1994/11/1
N2 - 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 and isotopic production to the cosmic-ray path length 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 γ-ray back-ground 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 α + α 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 cosmicray models for the early Galaxy.
AB - 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 and isotopic production to the cosmic-ray path length 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 γ-ray back-ground 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 α + α 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 cosmicray models for the early Galaxy.
KW - Cosmic rays
KW - Galaxy : evolution
KW - Nuclear reactions, nucleosynthesis, abundances
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U2 - 10.1086/174805
DO - 10.1086/174805
M3 - Article
AN - SCOPUS:12044259678
SN - 0004-637X
VL - 435
SP - 185
EP - 202
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 1
ER -