Convective neutron and s-process element production in deeply mixed envelopes

Abstract

view Abstract Citations (30) References (26) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Convective neutron and s-process element production in deeply mixed envelopes. Despain, K. H. Abstract Light-element reactions occurring at temperatures of 150 to 250 million K in deeply mixed red-giant convective envelopes are examined, and the production and capture of neutrons by light elements as well as heavy s-process elements are followed. The reaction network used is outlined, s-process reactions are analyzed, and results are presented for the first million seconds of convective mixing. It is shown that: (1) a deeply mixed envelope with a base temperature higher than 150 million K liberates energy equal to the binding energy of the envelope, which may lead to ejection of some portion of the envelope; (2) the major contributions to the energy generation come from O-18(p, alpha)N-15 and C-12(p, gamma)N-13 reactions and cause the formation of a steep gradient in the envelope hydrogen abundance at temperatures below 150 million K; (3) considerable nucleosynthesis occurs at the base of the envelope; and (4) the deeply mixed envelope is the site of a strong source of neutrons for base temperatures of at least 200 million K. Publication: The Astrophysical Journal Pub Date: March 1977 DOI: 10.1086/155103 Bibcode: 1977ApJ...212..774D Keywords: Heavy Elements; Light Elements; Neutrons; Nuclear Fusion; Particle Production; Red Giant Stars; Stellar Envelopes; Abundance; Astrophysics; Convective Flow; Hydrogen; Neutron Sources; Astrophysics full text sources ADS |