Developing system arrays for Nuclear Astrophysics with γ beams

Abstract

The advent of advanced facilities capable of generating high-intensity, high-resolution gamma-ray beams unlocks exciting opportunities for astrophysical research. Tunable gamma-ray beams with energies spanning from a few keV to tens of MeV offer the precision needed to measure extremely small cross sections (on the order of µb or smaller) critical to nuclear reactions in astrophysics. These measurements will provide essential data for accurately modeling astrophysical S-factors, which play a key role in understanding stellar evolution. In photonuclear reactions of astrophysical significance, photodissociations typically occur at photon energies slightly above particle emission thresholds, corresponding to typical stellar temperatures. Consequently, the emitted fragments exhibit low energies, generally ranging from a few hundred keV to a few MeV, which underscores the necessity of detectors with exceptionally low energy thresholds. Here, we highlight Asfin’s ongoing initiatives to design advanced detector arrays specifically tailored to address the challenges posed by these demanding measurements. An experimental campaign is currently in progress to assess the feasibility of measuring excitation functions and angular distributions using versatile silicon strip arrays, including LHASA and ELISSA.