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Changes in r-process abundances at late times

R. Surman·J. Engel
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Abstract

We explore changes in abundance patterns that occur late in the r process. As the neutrons available for capture begin to disappear, a quasiequilibrium funnel shifts material into the large peaks at A=130 and A=195, and into the rare-earth "bump" at A=160. A bit later, after the free-neutron abundance has dropped and beta-decay has begun to compete seriously with neutron capture, the peaks can widen. The degree of widening depends largely on neutron-capture rates near closed neutron shells and relatively close to stability. We identify particular nuclei the capture rates of which should be examined experimentally, perhaps at a radioactive beam facility.

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R. Surman, J. Engel. 2001-03-19. Changes in r-process abundances at late times. https://doi.org/10.1103/physrevc.64.035801

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