Evidence of double magicity of N=Z nuclei near the rp-process path

TL;DR

This paper provides experimental evidence that certain N=Z nuclei near the rp-process path exhibit double magicity due to shell gaps, impacting our understanding of nucleosynthesis and nuclear structure.

Contribution

It reports the discovery of double-magic character in specific N=Z nuclei near the rp-process path through isotope shift measurements.

Findings

N=Z nuclei $^{68}$Se, $^{72}$Kr, $^{76}$Sr, $^{80}$Zr show shell gaps in deformed space.

Pairing correlations vanish, indicating double-magicity.

Additional nuclei exhibit neutron magicity at N=34, 36, 38, 40.

Abstract

N=Z nuclei above Ni are understood to be waiting-point nuclei in the rp-process nucleosynthesis. Investigating the experimental isotope shifts in Kr isotopes near the proton drip-line, we have discovered that N=Z rp-process nuclei $^{68}$Se, $^{72}$Kr, $^{76}$Sr and $^{80}$Zr exhibit a significant shell gap both at the proton and neutron numbers in the deformed space with the consequence that pairing correlations for protons and neutrons vanish, thus lending a double-magic character to these nuclei. A significant number of nuclei in this region are also shown to exhibit neutron magicity at N = 34, 36, 38, and 40 in the deformed space.