No abstract

Background: Accurate knowledge of the 13 C(α,n) 16 O reaction cross section is important for the understanding of the s-process in AGB stars, since it is considered to be the main source of neutrons. The sub-threshold 1/2 + state at excitation energy of 6.356 MeV in 17 O has a strong influence on the reaction cross section at energies relevant for astrophysics. Several experiments have been performed to determine the contribution of this state to the 13 C(α, n) 16 O reaction rate. Nevertheless, significant discrepancies between different measurements remain.Purpose: The aim of this work is to investigate these discrepancies.Method: An 8 MeV 13 C beam (below the Coulomb barrier) was used to study the α-transfer However, some discrepancy with the most recent measurement using the Trojan Horse method remains.

Background: Many important α-particle induced reactions for nuclear astrophysics may only be

The γ-ray tracking array GRETINA was coupled to the S800 magnetic spectrometer for spectroscopy with fast beams of rare isotopes at the National Superconducting Cyclotron Laboratory on the campus of Michigan State University. We describe the technical details of this powerful setup and report on GRETINA's performance achieved with source and in-beam measurements. The γ-ray multiplicity encountered in experiments with fast beams is usually low, allowing for a simplified and efficient treatment of the data in the γ-ray analysis in terms of Doppler reconstruction and spectral quality. The results reported in this work were obtained from GRETINA consisting of 8 detector modules hosting four high-purity germanium crystals each. Currently, GRETINA consists of 10 detector modules.