Wednesday, October 29, 2014

Symmetries, Clusters and the Hoyle State

Moshe Gai (Connecticut)

(Previous seminar abstract:) Our recent measurements of new states in $^{12}$C allow the study the Rotation-Vibration spectrum of $^{12}$C from which evidence for a new (${\cal D}_{3h}$) geometrical symmetry emerges within the Algebraic Cluster Model (ACM). The data fit very well to the predicted (ground state) rotational band of an oblate equilateral triangular spinning top with a ${\cal D}_{3h}$ symmetry characterized by the sequence of states: $0^+, 2^+, 3^-, 4^\pm, 5^-$ with almost degenerate $4^+$ and $4^-$ (parity doublet) states. The ACM appears to open a new chapter in cluster physics of light nuclei and it presents an opportunity for further experimental investigation of light nuclei.