Accepted in ApJ, 22 pages, 5 figuresWe improve Standard Big Bang Nucleosynthesis (SBBN) calculations taking into account new nuclear physics analyses (Descouvemont et al. 2003). Using a Monte-Carlo technique, we calculate the abundances of light nuclei versus the baryon to photon ratio.The results concerning omegab are compared to relevant astrophysical and cosmological observations. Consistency between WMAP, SBBN results and D/H data strengthens the deduced baryon density and has interesting consequences on cosmic chemical evolution. A significant discrepancy between the calculated Li-7 deduced from WMAP and the Spite plateau is clearly revealed. To explain this discrepancy three possibilities are invoked : uncertainties on the Li abundance, surface alteration of Li in the course of stellar evolution or poor knowledge of the reaction rates related to Be-7 destruction. In particular, the possible role of the up to now neglected Be-7(d,p)2He-4 and Be-7(d,alpha)Li5 reactions is considered. The impressive advances in CMB observations provide a strong motivation for more efforts in experimental nuclear physics and high quality spectroscopy to keep BBN in pace

We report on a new measurement of the 14N(p,γ) 15O capture cross section at Ep=140 to 400 keV using the 400 kV LUNA accelerator facility at the Laboratori Nazionali del Gran Sasso (LNGS). The uncertainties have been reduced with respect to previous measurements and their analysis. We have analyzed the data using the R-matrix method and we find that the ground state transition accounts for about 15% of the total S-factor. The main contribution to the S-factor is given by the transition to the 6.79 MeV state. We find a total S(0)=1.7±0.2 keVb, in agreement with recent extrapolations. The result has important consequences for the solar neutrino spectrum as well as for the age of globular clusters. © 2004 Elsevier B.V. All rights reserved.info:eu-repo/semantics/publishe