The 0+ excited state of 12C at 7.65 MeV is named after Sir Fred Hoyle, who proposed its existence in order to account for high stellar abundances of carbon. Aside from this astrophysical significance, it is thought to possess a curious α-cluster structure. However, many questions still remain. To what extent can this state be described as three interacting α-particles, and if so, what geometric configuration do they take – a linear chain, equilateral triangle or something entirely different?
Two recent experiments have tested the validity of the α-cluster model by examining the ways that the Hoyle state decays. By precisely measuring the energies and angles of the three α-particles emitted during the decay, it was possible to differentiate between sequential (8Be + α) and direct (3α) processes. This talk details the experimental challenges associated with this measurement along with its implications for the structure of the Hoyle state.
Pizza at 11.45am outside WLC 108