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).
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
.
DOI: 10.3969/j.issn.1000-1565.2010.02.009
[1] BURBIDGE E M, BURBIDGE G R, FOWLER W A. Synthesis of the elements in stars [J]. Reviews of Modern Physics 1957, 29.
[2] GALLINO R, ARLANDINI C, BUSSO M. Evolution and nucleosynthesis in low-mass asymptotic giant branch stars.II.neutron capture and the s-process [J]. Astrophysical Journal 1998, 497.
[3] ARLANDINI C, KAPPELER F, WISSHAK K. Neutron capture in low-mass asymptotic giant branch stars:cross sections and abundance signatures [J]. Astrophysical Journal 1999, 525.
[4] James W. Truran, John J. Cowan, Catherine A Pilachowski, Christopher Sneden. Probing the Neutron-Capture Nucleosynthesis History of Galactic Matter [J]. Publications of the Astronomical Society of the Pacific 2002, 802(802).
[5] CLAYTON D D, WARD R A. S-process studies:exact evaluation of an exponential distribution of exposures [J]. Astrophysical Journal 1974, 193.
[6] PARDI M C, FERRINI F. Evolution of spiral galaxies, 4:The thick disk in the solar region as an intermediate collapse phase [J]. Astrophysical Journal 1995, 444.
[7] GORIELY S. A new approach to the canonical s-process model [J]. Astronomy and Astrophysics 1997, 327.
[8] MATHEWS G J, BAZAN G, COWAN J J. Evolution of heavy-element abundances as a constraint on sites for neutron-capture nucleosynthesis [J]. Astrophysical Journal 1992, 391.
[9] ULRICH R K. In explosive nucleosynthesis [M]. Austin:University of Texas Press 1973.
[10] STRANIERO O, DOMINGUEZ I, CRISTALLO R. Low-mass AGB stellar models for 0.003≤Z≤0.02:basic formulae for nucleosynthesis calculations [J]. Publications of the Astronomical Society of Australia 2003, 20.
[11] RENZINI A, VOLI M. Advanced evolutionary stages of intermediate-mass stars:Evolution of surface compositions [J]. Astronomy and Astrophysics 1981, 94.
[12] MARIGO P, BRESSAN A, CHIOSI C. The TP-AGB phase:a new model [J]. Astronomy and Astrophysics 1996, 313.
[13] RENZINI A, VOLI M. Advanced evolutionary stages of intermediate-mass stars.I-evolution of surface compositions [J]. Astronomy and Astrophysics 1981, 94.
