Abstract
Complete-kinematics data from a measurement of the decay of 12C* into three α particles are analyzed. Owing to the symmetries of the three-α final state, the Dalitz plot exhibits nodes (regions of vanishing intensity) characteristic of the spin and parity of the system. Exploiting this property, we argue that a broad unidentified structure in the excitation spectrum around 12.4 MeV is likely to have unnatural spin–parity and J ≥ 4.
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Kirsebom, O.S. Decay of 12C* into Three α Particles. Few-Body Syst 54, 755–759 (2013). https://doi.org/10.1007/s00601-012-0441-z
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DOI: https://doi.org/10.1007/s00601-012-0441-z