EPJ Web of Conferences (Mar 2014)
Search for rotational state of Hoyle state in complete kinematic experiment 12C(α, α′) 3α
Abstract
An excited state of 12C having excitation energy (Ex) 9.65 ± 0.02 MeV and width (FWHM) 607 ± 55 keV, which decays to three α particles via Hoyle state (Ex = 7.65 MeV), has been directly identified in the exclusive inelastic scattering of 60 MeV 4He on 12C, measured in coincidence with the recoiling 12C Hoyle state (decaying mostly as 12C* → 8Begs → α → α + α + α) by event-by-event kinematic reconstruction of the completely detected (4α) events. This state is likely to be a candidate for 22+ first excited of Hoyle state.