Distributions of Neutron Exposures in the Galaxy

doi:10.3969/j.issn.1000-1565.2010.02.009

Abstract

Abstract: The author introduce a new concept, the distribution function of neutron exposures in the Galaxy ρ_(gal)(t,τ), to study the chemical evolution characteristics of the Galaxy for s-process nuclei. Using the three component model for the chemical evolution of the Galaxy, we get the evolution functions of ρ_(gal)(t,τ) which include the distribution function of neutron exposures in the AGB stars ρ_(AGB)(τ)·At t=t_⊙, we adopt the ρ_(AGB)(τ) as exponential distribution and obtain the distribution function of neutron exposures in the solar system ρ_(Sun)(τ).

Key words: chemical evolution of galaxy, AGB stars, nucleosynthesis, neutron exposure

CLC Number:

P142

LIU Yong-li,CUI Wen-yuan,ZHANG Jiang,LIU Hu-guo. Distributions of Neutron Exposures in the Galaxy[J]. Journal of Hebei University (Natural Science Edition), 2010, 30(2): 146-151.

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