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Title: Branchings in the {gamma} process path revisited

Abstract

The location of the ({gamma},p)/({gamma},n) and ({gamma},{alpha})/({gamma},n) line at {gamma} process temperatures is discussed, using updated reaction rates based on global Hauser-Feshbach calculations. The results can be directly compared with classic {gamma} process discussions. The nuclei exhibiting the largest sensitivity to uncertainties in nuclear structure and reaction parameters are specified, and suggestions for experiments are made. Additionally, the effect of employing two recent global {alpha}+nucleus potentials is discussed. It is found that branchings at higher mass depend more sensitively on these potentials. The case of {sup 146}Sm/{sup 144}Sm production is addressed separately. Also, in this case the more recent {alpha}+nucleus potentials seem to address the issues concerning the production of these Sm isotopes in massive stars. In conclusion, it is found that it is unlikely that the calculated underproduction of p nuclides in the Mo-Ru region is due to nuclear physics deficiencies but that problems at higher mass number may still be solved by improved nuclear input.

Authors:
 [1]
  1. Departement fuer Physik und Astronomie, Universitaet Basel, CH-4056 Basel (Switzerland)
Publication Date:
OSTI Identifier:
20771233
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 73; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevC.73.015804; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; BRANCHING RATIO; HAUSER-FESHBACH THEORY; NEUTRONS; NUCLEAR POTENTIAL; NUCLEAR REACTION KINETICS; NUCLEAR STRUCTURE; PHOTONUCLEAR REACTIONS; PROTONS; SAMARIUM 144; SAMARIUM 146

Citation Formats

Rauscher, Thomas. Branchings in the {gamma} process path revisited. United States: N. p., 2006. Web. doi:10.1103/PhysRevC.73.015804.
Rauscher, Thomas. Branchings in the {gamma} process path revisited. United States. doi:10.1103/PhysRevC.73.015804.
Rauscher, Thomas. Sun . "Branchings in the {gamma} process path revisited". United States. doi:10.1103/PhysRevC.73.015804.
@article{osti_20771233,
title = {Branchings in the {gamma} process path revisited},
author = {Rauscher, Thomas},
abstractNote = {The location of the ({gamma},p)/({gamma},n) and ({gamma},{alpha})/({gamma},n) line at {gamma} process temperatures is discussed, using updated reaction rates based on global Hauser-Feshbach calculations. The results can be directly compared with classic {gamma} process discussions. The nuclei exhibiting the largest sensitivity to uncertainties in nuclear structure and reaction parameters are specified, and suggestions for experiments are made. Additionally, the effect of employing two recent global {alpha}+nucleus potentials is discussed. It is found that branchings at higher mass depend more sensitively on these potentials. The case of {sup 146}Sm/{sup 144}Sm production is addressed separately. Also, in this case the more recent {alpha}+nucleus potentials seem to address the issues concerning the production of these Sm isotopes in massive stars. In conclusion, it is found that it is unlikely that the calculated underproduction of p nuclides in the Mo-Ru region is due to nuclear physics deficiencies but that problems at higher mass number may still be solved by improved nuclear input.},
doi = {10.1103/PhysRevC.73.015804},
journal = {Physical Review. C, Nuclear Physics},
number = 1,
volume = 73,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2006},
month = {Sun Jan 15 00:00:00 EST 2006}
}
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