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The resoneut detector setup is described, which was developed for resonance spectroscopy using (d,n) reactions with radioactive beams in inverse kinematics and at energies around the Coulomb barrier. The goal of experiments with this setup is to determine the spectrum and proton-transfer strengths of the low-lying resonances, which have an impact on astrophysical reaction rates. The setup is optimized for l = 0 proton transfers in inverse kinematics, for which most neutrons are emitted at backward angles with energies in the 80–300 keV range. The detector system is comprised of 9 p-terphenyl scintillators as neutron detectors, two annular silicon-strip detectors for light charged particles, one position-resolving gas ionization chamber for heavy ion detection, and a barrel of NaI-detectors for the detection of γ -rays. The detector commissioning and performance characteristics are described with an emphasis on the neutron-detector components.

The destruction of 7 Li and 7 Be in astrophysical environments is essential for understanding several stellar and cosmological processes and is not well understood, though earlier 7 Li + 3 He experiments have been performed [1]. The primordial abundance of 7 Li after Big Bang Nucleosynthesis (BBN) plays a major role in our understanding of the early universe [2]. The value of the baryon to photon ratio (η) deduced from BBN combined with measurements of the cosmic microwave background provide some of the strongest and earliest evidence for the existance of non-baryonic dark matter [2]. The destruction of 7 Be during the hot-pp cycle may alter our conclusions on the production of carbon in this process, which is thought to compete with the triple-α process for the production of 12 C, as the reaction 7 Be( 3 He, 2α)2p competes with 7 Be( 4 He, γ) 11 C and may reduce carbon production [3]. These stellar and cosmological environments involve high temperatures, and thus, effective burning energies (Gamow windows) that are quite high. Experiments using 7 Be targets inevitably involve interactions with 7 Li as background due to the 7 Li daughters from the beta decay of 7 Be. The experiments were performed at the Weizmann Institute VDG Laboratory using 3 He beams from 390 keV to 1130 keV on 7 LiF foil targets and 7 Be implanted targets. Results from measurements using 10 μg 7 LiF foil targets will be discussed.