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The astrophysically relevant 3 He ( d , p ) 4 He reaction was indirectly studied by means of the Trojan Horse Method applied to the 6 Li ( 3 He , pα ) 4 He three body process performed at 5 and 6 MeV. The bare astrophysical S(E)-factor extracted in Modified Plane Wave Born Approximation was compared with the free behaviour and an independent estimate of the screening potential was obtained, confirming the discrepancy with the adiabatic limit.

The 6He+6, 7Li and 6He+12C reactions have been measured using a 18.0 MeV 6He beam of the radioactive beam facility in Louvain-la-Neuve. Charged particles were detected in three large-area silicon strip detector arreys (320 strip detectors in total) 300 microm thick. Angular distributions have been measured for the elastic scattering and a number of two-body reactions. Pick-up of deuterons, tritons and alpha-particles from 6Li and 7Li targets were clearly seen. In triple coincident events, the 6He+6Li->6He+alpha+d, 6He+6Li->2alpha+t+n, 6He+7Li->6He+alpha+t, and 6He+12C->10Be*+2alpha reactions were clearly extracted and, assuming sequential decay mechanism, cluster states of 6Li, 7Li, 9Be, 10Be and 14C were recognized and discussed.

The Trojan-Horse Method has been applied to the three-bodyd( 6 Li,α 3 He)n break-up reaction in order to extract the bare nucleus S(E) factor for the 6 Li(p,α) 3 He down to astrophysical energies.

The 6 He+ 12 C elastic and inelastic scattering and the 6 He+ 12 C→ α + 14 C reaction have been measured using a 18.0 MeV 6 He beam. Experimental results for the elastic scattering are in fair agreement with optical model predictions, using the potentials found in the analysis of 6 Li scattering on 12 C at similar energies. In triple coincidences, the 6 He+ 12 C→ 10 Be+2 α reactions were clearly seen, with the 10 Be nucleus left in ground and several excited states. The dominant mechanism of this reaction is sequential decay through cluster states of 14 C.

The Trojan Horse Method has been applied to study the 7 Li ( p , α ) 4 He and 6 ( Li ( d , α ) 4 He reactions through the 7 Li(d, αα)n and 6 Li( 6 Li, αα) 4 He three body processes, respectively. The electron screening potential deduced from these experiments is much larger than the adiabatic approximation prediction for both cases; the systematic discrepancy between data and theoretical predictions is thus confirmed. Astrophysical implications of these measurements are also discussed.

The 15O(α,γ)19Ne reaction is generally considered as a potential breakout reaction from the hot CNO cycle. Under nova conditions, the reaction rate is dominated by a single sub-Coulomb resonance at Ec.m.=504 keV which corresponds to a 19Ne excitation energy of ER=4.033 MeV. Results from a d(18Ne,19Ne)p experiment show that states of astrophysical interest are populated in this reaction. An upper limit for the α-branching ratio of the 4.033 MeV state was identified and branching ratios for other states in 19Ne were found to be in good agreement with stable beam based results.