Reaction Measurements for the Weak r-Process Following Core-Collapse Supernova Explosions

The multi-messenger observation of a binary neutron star merger has greatly advanced our understanding of heavy element synthesis via the rapid neutron capture process (r-process). However, studies of ultra-metal-poor stars offer compelling evidence for an additional r-process site responsible for creating the lightest heavy elements. Neutrino-driven winds after core-collapse supernovae have emerged as a potential candidate for the production of these lighter r-process elements, commonly referred to as the weak r-process. Recent sensitivity studies have highlighted that uncertainties in (α,n) reaction rates significantly hinder accurate predictions of elemental abundances in this astrophysical environment. Unfortunately, our understanding of these crucial reaction rates remains limited, largely due to the challenges posed by low-intensity radioactive beams and inherently small cross sections.



Fortunately, recent advancements in experimental techniques, coupled with the growing capabilities of radioactive ion beam facilities, have opened up opportunities for the experimental investigation of these crucial reactions. In this talk, I will discuss the latest experimental efforts aimed at constraining these reaction rates, including the work done using the Multi-Sampling Ionization Chamber (MUSIC) detector.