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The 12C(12C,p)23Na and 12C(12C, $\alpha$ )20Ne fusion reactions are among the most important in stellar evolution since they determine the destiny of massive ( $ M \simeq 8-10 M_{\odot}$ ) stars. However, experimental low-energy investigations of such reactions are significantly hampered by ubiquitous natural hydrogen and deuterium contaminants in the carbon targets. The associated beam-induced background completely masks the reaction products of interest thus preventing cross-section measurements at the relevant energies of astrophysical interest, $E_{\mathrm{cm}} < 2$ MeV. In this work, we report about an investigation aimed at assessing possible deuterium reductions on both natural graphite and Highly Ordered Pyrolytic Graphite targets as a function of target temperature. Our results indicate that reductions up to about 80% can be attained on both targets in the temperature range investigated, $ T \simeq 200-1200 {}^{\circ}$ C. A further reduction by a factor of 2.5 in absolute deuterium content is observed when the scattering chamber is surrounded by a dry nitrogen atmosphere so as to minimise light-particles uptake within the chamber rest gas (and thus on target) through air leaks. The results from this study will inform the choice of optimal experimental conditions and procedures for improved measurements of the 12C + 12C reactions cross-sections at the low energies of astrophysical interest.

7Be(p, $\gamma$ )8B has an important role in nuclear astrophysics, having a direct impact on both the high energy component of solar neutrinos and the 7Li abundance after the Big Bang Nucleosynthesis. All direct measurements providing useful information on this reaction so far used the same approach, i.e. a proton beam on a radioactive 7Be target. The overall precision and accuracy of the estimate of the astrophysical rate of this reaction are limited by the discrepancy between the results of existing measurements, possibly due to the complicated stoichiometry and beam induced deterioration of the radioactive targets. The ERNA (European Recoil separator for Nuclear Astrophysics) collaboration planned a new experiment in inverse kinematics exploiting the intense 7Be beam available at CIRCE (Center for Isotopic Research on Cultural and Environmental heritage), Caserta, Italy. The 8B recoils are produced in a windowless hydrogen gas target and detected after the efficient mass separation provided by ERNA. Here we present the commissioning of the experimental setup and a first cross section measurement at $E_{\mathrm{cm}}\approx 812$ keV.