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Simulations of explosive nucleosynthesis in novae predict the production of 22Na, a key astronomical observable to constrain nova models. Its gamma-ray line at 1.275 MeV has not yet been observed by the gamma-ray space telescopes. The 20Ne/22Ne ratio in presolar grains, a possible tool to identify nova grains, also depends on 22Na produced. Uncertainties on its yield in classical novae currently originate from the rate of the 22Na(p, γ)23Mg reaction. At peak novae temperatures, this reaction is dominated by a resonance at ER=0.204 MeV, corresponding to the Ex=7.785 MeV excited state in 23Mg. The resonance strengths measured so far disagree by one order of magnitude. An experiment has been performed at GANIL to measure the lifetime and the proton branching ratio of this key state, with a femtosecond resolution for the former. The reactions populating states in 23Mg have been studied with a high resolution detection set-up, i.e. the particle VAMOS, SPIDER and gamma tracking AGATA spectrometers, allowing the measurements of lifetimes and proton branchings. We present here a comparison between experimental results and shell-model calculations, that allowed us to assign the spin and parity of the key state. Rather small values obtained for reduced M1 matrix elements, M(M1) ≲ 0.5 µN, and proton spectroscopic factors, C2Sp

The Resonant Elastic Scattering (RES) method has been used at GANIL with Radioactive Ions Beams (RIB) in order to study important unbound states. Three examples of studies are given: the first one is related to the important astrophysical reaction 18F(p,α)15O, the second one to the two-proton radioactivity of 19Mg, and the third one to the prediction of the existence of a narrow state in the unbound nucleus 15F. The three experiments have benefited from high quality radioactive beams produced by the Spiral Facility.

In this work we present the preliminary results of analysing the 46Mn β+ decay channel as a way to study the 45V(p, γ)46Cr reaction. 46Mn was selected among other species in the cocktail beam delivered by the LISE fragment separator at GANIL (Caen, France) in order to study its beta decay and the excited states of its daughter nucleus 46Cr. As part of the validation process we present the 46Mn half-life, the proton and gamma emission peaks related to the 46Mn decay and compare them with the results from previous works.

The proton, deuteron and alpha induced reactions are of a great interest for the assessment of induced radioactivity of accelerator components, targets and beam stoppers as well as isotope production for medicine and also to nuclear astrophysics. We present a new irradiation chamber for activation measurements, that forms a prolongation of long-term experimental activities using stacked-foil activation technique in NPI CAS, Řež. The chamber is based on an airlock system and is coupled to a pneumatic transfer system delivered by KIT Karlsruhe. This system is installed in GANIL/SPIRAL2-NFS and will be used for proton, deuteron and alpha particle activation measurements with long- and short-lived isotopes.

Elastic scattering of nuclei at energies typically below 10 MeV/nucleon can be used as a powerful method for studying nuclear spectroscopy. Resonances are observed in the excitation function, corresponding to unbound states in the compound nucleus. The analysis of the shape of these resonances can provide the excitation energy, the total width, the partial width, and the spin of the excited states.