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We report on the measurement of the ^{7}Be(n,p)^{7}Li cross section from thermal to approximately 325 keV neutron energy, performed in the high-flux experimental area (EAR2) of the n_TOF facility at CERN. This reaction plays a key role in the lithium yield of the big bang nucleosynthesis (BBN) for standard cosmology. The only two previous time-of-flight measurements performed on this reaction did not cover the energy window of interest for BBN, and they showed a large discrepancy between each other. The measurement was performed with a Si telescope and a high-purity sample produced by implantation of a ^{7}Be ion beam at the ISOLDE facility at CERN. While a significantly higher cross section is found at low energy, relative to current evaluations, in the region of BBN interest, the present results are consistent with the values inferred from the time-reversal ^{7}Li(p,n)^{7}Be reaction, thus yielding only a relatively minor improvement on the so-called cosmological lithium problem. The relevance of these results on the near-threshold neutron production in the p+^{7}Li reaction is also discussed.

A high-resolution study of dipole transitions to bound states up to 10 MeV in the f p-shell nuclei 56 Fe and 58 Ni was performed by means of the nuclear resonance fluorescence method. Unpolarized and partially linearly polarized bremsstrahlung photons with different end point energies ͑6.5, 10, and 12 MeV͒ were used to determine excitation energies, spins, parities, and transition widths of more than 60 levels observed in each nucleus between 2 and 10 MeV. The vast majority of the observed transitions are dipole ones and to the strongest of them an E1 assignment could be given. The E1 strength distribution shows a high concentration around 8.2 MeV that may be connected with the E1 pygmy resonance in heavier nuclei. The M 1 spin-flip strength shows a concentration around 8.7 MeV in 58 Ni. On the contrary, in 56 Fe its distribution is rather flat. The observed M 1 strength is weak in both nuclei. A study was made of the feeding and branching of the observed levels. Calculations were performed for these nuclei in the framework of the quasiparticle phonon model and a comparison with experimental results is made. Apart from the strength, experimental and calculated results agree quite well and information about a scissorslike mode in 56 Fe and a 1 Ϫ two-phonon state in 58 Ni could be extracted.

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At the neutron Lime-of-flight facility n_TOF at CERN a new vertical beam line was constructed in 2014, in order to extend the experimental possibilities at this facility to an even wider range of challenging cross-section measurements of interest in astrophysics, nuclear technology and medical physics. The design of the beam line and the experimental hall was based on FLUKA Monte Carlo simulations, aiming at maximizing the neutron flux, reducing the beam halo and minimizing the background from neutrons interacting with the collimator or back-scattered in the beam dump. \ud The present paper gives an overview on the design of the beam line and the relevant elements and provides an outlook on the expected performance regarding the neutron beam intensity, shape and energy resolution, as well as the neutron and photon backgroundsPostprint (author's final draft

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