The Hoyle Family: The search for alpha-condensate states in light nuclei

Abstract

Our present understanding of the structure of the Hoyle state in ${}^{12}$C and other near-threshold states in $\alpha$-conjugate nuclei is reviewed in the framework of the $\alpha$-condensate model. The ${}^{12}$C Hoyle state, in particular, is a candidate for $\alpha$-condensation, due to its large radius and $\alpha$-cluster structure. The predicted features of nuclear $\alpha$-particle condensates are reviewed along with a discussion of their experimental indicators, with a focus on precision break-up measurements. Two experiments are discussed in detail, firstly concerning the break-up of ${}^{12}$C and then the decays of heavier nuclei. With more theoretical input, and increasingly complex detector setups, precision break-up measurements can, in principle, provide insight into the structures of states in $\alpha$-conjugate nuclei. However, the commonly-held belief that the decay of a condensate state will result in $N$ $\alpha$-particles is challenged. We further conclude that unambiguously characterising excited states built on $\alpha$-condensates is difficult, despite improvements in detector technology.

Submitted to Few-Body Systems on 9th November 2019

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• Evidence for Triangular D_3h Symmetry in 12C
• Status of Alpha-Particle Condensate Structure of the Hoyle State
• High precision probe of the fully sequential decay width of the Hoyle state in ${}^{12}$C
• Alpha particle clusters and their condensation in nuclear systems
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Cited by in corpus (6)

• Almost medium-free measurement of the Hoyle state direct-decay component with a TPC
• Correlation in formation of ${}^8$Be nuclei and $\alpha$-particles in fragmentation of relativistic nuclei
• Prospects of searching for unstable nucleus states in relativistic nuclear fragmentation
• Signatures of $\alpha$-clustering in ${}^{12}$C and ${}^{13}$C
• Self-consistent strong screening applied to thermonuclear reactions
• The ${}^8$Be nucleus and the Hoyle state in dissociation of relativistic nuclei