The transfer reaction 11 B( 13 N, 12 C) 12 C

Summary The transfer reaction 11 B( 13 N, 12 C) 12 C * has been investigated at the two laboratory energies E lab =45 MeV and E lab =29.5 MeV. Particle-γ and particleparticle coincidences have been measured. The coincidence between a heavy ion and the 15.1 MeV γ-ray emitted from 12 C * shows transition to the 12 C gs + 12 C * 15.1 and 12 C * 4.44 + 12 C * 15.1 exit channels. These indicate the mixed ground-state structure of 13 N. DWBA calculations have also been performed. Analysis of particle-particle coincidence data revealed the presence of transfer channels also to unbound states of 12 C such as 12 C gs + 12 C * (E * >7.64 MeV) and 12 C * 4.44 + 12 C * (E * >7.64 MeV). The angular distributions have been extracted for these two channels. Six-alpha-particle events have also been analyzed. Some of these events have been identified as coming from 11 B( 13 N, 12 C * ) 12 C * reaction. An enhancement in the six-α cross-section is observed at an excitation energy for the compound nucleus 24 Mg close to the 46 MeV resonances observed in 12 C + 12 C inelastic scattering. These six-alphas events are generated mostly from the break-up of 12 C(3 - 1 ) + 12 C(3 - 1 ) and therefore seems not to be associated with the six-alphas chain state.