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A γ-ray spectroscopic study of 10B is reported. Excited states in 10B were populated in inelastic proton scattering and their γ-decays were measured with the ELIFANT array, a state-of-the-art spectrometer with large volume LaBr3:Ce and CeBr3 detectors placed in anti-Compton shields and having unprecedented efficiency for high-energy γ rays. A few weak transitions were observed in the experiment, namely M3 transition between Jπ, T = 0+1, 1 isobaric analog state to the Jπ, T = 3+1,0 ground state and E2 transition between the Jπ, T = 2+1,0 state and the isobaric analog state. The results are compared to a new set of ab initio no-core shell model calculation using the newest version of the local position-space chiral N3LO nucleon-nucleon interaction, which correctly reproduces the spectrum of the excited states in 10B, a problem of the theory in previous years.

A high-and-flat efficiency moderated neutron detection array of 3He counters has been recently developed for photoneutron cross section measurements at the future ELI-NP gamma-ray beam source. We have designed a three rings geometry of 31 counters with a ˜37% efficiency flat within 5% in the 10 keV to 5 MeV neutron energy interval. A commissioning experiment was performed using proton beams delivered by the 9 MV Tandem accelerator of IFIN-HH. We measured the neutron production cross sections for proton induced reactions on nat Cu and 27Al. The (p, xn) reactions on nat Cu were investigated in the 4.5 MeV to 14 MeV proton energy range with 250 keV steps, using pulsed and continuous proton beams. The low energy measurements below 10 MeV served to validate the detection efficiency calibration against well-known natCu(p, n) cross sections. The 27Al(p, n) reaction was investigated in the 5.8 MeV to 6.75 MeV energy range with 5 keV steps. Preliminary cross section results are here compared with preceding data.

Absolute cross sections for the 86Sr(α,n)89Zr reaction at energies close to the Gamow window are reported. Three thin SrF2 targets were irradiated using the 9 MV Tandem facility in IFIN-HH Bucharest that delivered α beams for the activation process. Two high-purity Germanium detectors were used to measure the induced activity of 89Zr in a low background environment. The experimental results are in very good agreement with Hauser-Feshbach statistical model calculations performed with the TALYS code.