Threshold Phenomena in Nuclei: From Superradiance to Alpha Clustering
Prof. Alexander Volya
Florida State University
The atomic nucleus is a remarkable natural quantum many-body system, central to many modern research areas, from quantum entanglement to astrophysics. In this presentation, I will discuss our recent studies on the behavior of quantum many-body systems near decay thresholds, both below and above, and explore the associated dynamics of unstable quantum systems. A striking example is threshold attraction, where near-threshold states emerge with properties aligned with corresponding reaction channels, as exemplified by alpha clustering and few-body correlations. In decaying systems, coupling to the continuum of reaction states and the overlapping nature of resonances alters the structural properties of states, leading to superradiance, where states decouple into broad and narrow resonances.Through theoretical configuration interaction studies and examples of alpha clustering, I will present both theoretical and experimental manifestations of these phenomena in nuclear systems. Viewing the nucleus as an open quantum system deepens our understanding of clustering dynamics and the emergence of collective degrees of freedom. Recent advancements in experimental techniques have enabled the observation and study of these threshold phenomena—such as superradiance, threshold attraction, and alpha clustering—in a more quantitative and precise way.
Hosted by Prof. Wiescher