Common astrophysical site for all r-process abundance peaks

Determine whether the three canonical r-process abundance peaks at mass numbers A ≈ 80, 130, and 195—each associated with closed neutron shells N = 50, 82, and 126—originate from a single astrophysical site or require multiple distinct astrophysical sites.

Background

The rapid neutron-capture (r-) process produces heavy nuclei far from stability and yields characteristic abundance peaks at A ≈ 80, 130, and 195, corresponding to magic neutron numbers N = 50, 82, and 126. Identifying the astrophysical environment(s) responsible for these peaks is central to understanding heavy element synthesis.

This paper discusses candidate r-process sites, including core-collapse supernovae and neutron-star mergers (kilonovae), and emphasizes the co-production of elements near the A ≈ 130 peak such as tellurium (Z = 52) and iodine (Z = 53). Clarifying whether a single site can account for all three peaks affects interpretations of the origins of biologically essential heavy elements like iodine and bromine.

References

Whether all three abundance peaks owe their origins to the same astrophysical site is an open question, e.g. .

— Do we Owe our Existence to Gravitational Waves? (2402.03593 - Ellis et al., 6 Feb 2024) in Section “Heavy Element Production via the r-Process”