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In a recent experiment performed at Triumf using the Dragon 0° spectrometer and its associated BGO array we have measured for the first time the full gamma decay of the radiative capture channel close to the Coulomb barrier. This measurement has been performed at 3 energies Ecm = 8.5, 8.8 and 9 MeV. We have extracted a radiative capture cross section more than five times larger than what had been previously observed. A selective contribution of the entrance spins 5- and 6+ has also been evidenced whereas 1- to 3- spins are predicted to be predominant by coupled-channel calculations. At Ecm = 9 MeV, stronger structural behaviour appears which is characterised by a larger total cross section and also by the particularly strong feeding of the 28Si prolate 4+ state at 9.16 MeV. This level is explained by several models in terms of 12C-16O cluster sub-structure. Our data is compared to such cluster-model predictions and the agreement is quite good. [ABSTRACT FROM AUTHOR]

The 12C(16O,γ)28Si radiative capture reaction has been studied at energies close to the Coulomb barrier at Triumf (Vancouver) using the Dragon spectrometer and its associated BGO array. It has been observed that the γ decay flux proceeds mainly via states around 10–11 MeV and via the direct feeding of the 28Si 31- (6879 keV) and 42+ (6888 keV) deformed states. A discussion is presented about this selective feeding as well as perspectives for the use of novel detection systems for the study of light heavy-ion radiative capture reactions. [ABSTRACT FROM AUTHOR]

Resonances in light heavy-ion collisions have been observed in systems with a small number of open channels. Very narrow resonances have been reported in the 24Mg+24Mg and 12C+12C cases for which the results of recent experiments on their decay modes will be presented. Special emphasis will be given to the 12C+12C reaction where weak absorption allows the observation of resonant and refractive effects over a large bombarding energy range. The nature of recently observed sub-coulomb resonances will also be raised. [ABSTRACT FROM AUTHOR]

The narrow (Γ=170 keV) and high spin (Jπ=36+) resonance in the 24Mg + 24Mg reaction at ECM= 45.7 MeV has been associated with a hyperdeformed molecular state in 48Cr. Such a description has important consequences for the resonance decay into the favored inelastic channels. Through fragment-γ coincidence measurements performed ON and OFF resonance using the PRISMA-CLARA array, we have identified the 24Mg states selectively populated: the 2+ and 4+ members of the ground state band. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Resonances in the 12C(16O,γ)28Si radiative capture process at energies around the Coulomb barrier have been probed using the very selective 0° Dragon spectrometer at Triumf and its associated BGO γ-array. For the first time the full level scheme involved in this process has been measured and shows previously unobserved γ-decay to doorway states around 11 MeV in 28Si. [ABSTRACT FROM AUTHOR]