Transition from direct to sequential two-proton decay in $s$-$d$ shell nuclei

TL;DR

This paper introduces an improved model for studying two-proton decay mechanisms in nuclei, demonstrating its effectiveness through examples and showing how decay dynamics can reveal properties of nuclear states.

Contribution

The paper presents a generalized direct-decay model that accurately describes three-body correlations in two-proton decays and applies it to analyze transition dynamics in $s$-$d$ shell nuclei.

Findings

Transition dynamics are highly probable beyond the proton dripline.

The model allows extraction of the width of the core+$p$ subsystem resonance.

Properties of $^{14}$F and $^{29}$Cl ground states are derived from decay data.

Abstract

Transitions among different mechanisms of two-proton decay are studied in general. The introduced improved direct-decay model generalizes the semi-analytical models used before and provides flawless phenomenological description of three-body correlations in $2p$ decays. This is demonstrated by examples of the low-lying $^{16}$Ne state decays. Different forms of transition dynamic are shown to be highly probable beyond the proton dripline for the $s$-$d$ shell nuclei. It is demonstrated that transition dynamic of $2p$ emitters can provide means for extraction of a width of the ground-state resonance of a core+$p$ subsystem of the core+$2p$ system. Practical applicability of the method is demonstrated by properties of the $^{14}$F ground state derived from the $^{15}\mbox{Ne}\rightarrow ^{\,13\!\!}\mbox{O}+2p$ decay data and of the $^{29}$Cl ground state derived from the $^{30}\mbox{Ar}\rightarrow ^{\,28\!\!}\mbox{S}+2p$ decay data.