Alpha-decay of excited states in 13C and 14C

Measurements of the 14C(13C, 13C[9Be+α]) and 14C(13C, 14C[10Be+α]) break-up reactions have been made at beam energies of 77.8, 112.25 and 119.25 MeV. The studies were performed with two charged particle telescopes which measured the energy, mass, charge and emission angle of each detected particle. These data provide evidence for α-decaying states at 13.2(1), (13.6(2)), 14.2(1), 15.0(1) and 16.0(1) MeV in 13C and 14.9(1), 15.9(1), 16.5(1), 18.5(3), (19.1(2)), (19.9(2)) and 21.3(4) MeV in 14C. The 13C angular distributions were analysed and give an indication of the parity of the various states populated. These data are interpreted from the perspective of the α-cluster structure of 13,14C, and indicate the preferential population of oblate type cluster states.