Accession Number : AD0612850

Title :   NUCLEOSYNTHESIS OF HEAVY ELEMENTS BY NEUTRON CAPTURE,

Corporate Author : CALIFORNIA INST OF TECH PASADENA

Personal Author(s) : Seeger,Philip A. ; Fowler,William A. ; Clayton,Donald D.

Report Date : 14 JUL 1964

Pagination or Media Count : 48

Abstract : Nucleosynthesis of elements heavier than the iron group by neutron capture on both slow and fast time scales is evaluated. The s-process calculations of Clayton, Fowler, Hull, and Zimmerman (Ann. Phys. 12:331, 1961) were revised to include more recent experimental results on abundances and neutron capture cross-sections. The solar-system s-process abundances indicate a history of neutron exposure distributions characterized by decreasing probability of high integrated flux; an exponential exposure distribution is extracted. Estimates are made of the s-process contribution to each isotopic abundance; a table gives the amounts of elements produced by each process in the solar-system material. The r-process calculations are carried out using a semi-empirical atomic-mass law to determine neutron-binding energies and beta-decay probabilities. The solar-system r-process material has probably been synthesized in two distinct types of environments. (Author)

Descriptors :   (*SOLAR SYSTEM, NUCLEAR REACTIONS), (*NUCLEAR REACTIONS, SOLAR SYSTEM), (*NEUTRON CAPTURE, SOLAR SYSTEM), SYNTHESIS, METEORITES, NEUTRON CROSS SECTIONS, NEUTRON FLUX, NUCLEAR BINDING ENERGY, NUCLEAR ENERGY LEVELS, BETA DECAY, NUCLEAR ISOBARS, DISTRIBUTION, RADIOACTIVE DECAY

Distribution Statement : APPROVED FOR PUBLIC RELEASE