Ponente
Descripción
The unique structure of the halo nucleus $^{11}$Be continues to challenge the traditional understanding of nuclear stability and weak interaction dynamics. In this nuclei, the characteristics of a weakly-bound single-particle orbital wave function, defined by its closeness to the confinement threshold, are central to many nuclear phenomena. The weak binding of the halo neutron in $^{11}$Be, positioned near the proton emission threshold, creates a quantum environment where the halo neutron’s wave function extends into the continuum. This open quantum system behavior allows for an enhanced decay channel via a narrow resonant state closer to the daughter nuclei $^{11}$B proton separation energy, which significantly increases the proton emission branching ratio. Resulting in a considerable branching ratio of proton emission in a neutron rich nuclei, which is in actual experimental discrepancy with theoretical models.
This coupling to continuum states manifests as a Fano resonance phenomenon, where the interference between the discrete resonant state and the background continuum produces asymmetric line shapes in nuclear spectroscopy. Moreover, weak binding behavior significantly affects our insights into the evolution of single-particle orbitals, the positioning and significance of the light particle drip lines, and the emergence of nuclear halo states. This fact, opens the possibility of more exotic decay modes, such as the hypothesized dark decay, such process would evade direct detection, representing an intriguing interface between nuclear structure physics and particle physics beyond the standard model
