A newly observed state in 12C – characterisation and consequences

Measurements of the 12C(4He,4He)12C* reaction at 40 MeV were performed using a charged-particle detector array composed of four double-sided silicon strip detectors. Resonances in 12 C were reconstructed with the requirement that the a-decay proceeded first via the 8 Be ground state. Of primary significance was the population of the 13.3 and 22.4 MeV resonances, the latter, observed for the first time in this measurement. By using the angular correlation technique the spins of the resonances, have been established as Jπ 4+ and Jπ=5− respectively.