University of Tennessee student Matt Christie has been selected for a DOE SCGSR Award, to work with Steve Pain at ORNL. Matt’s proposal is based on developing an experiment to constrain the radiative branching of the Hoyle state – the excited state in carbon-12 that is the main pathway to the formation of carbon from three alpha particles in stellar environments – ultimately the main source of carbon necessary for life on earth. Recent measurements have highlighted a discrepancy in the radiative branching ratio for the Hoyle state, which impacts the cross section of this reaction, and hence our understanding of stellar evolution. To resolve this discrepancy, Matt’s experimental plans are to use the resolution and efficiency of the GODDESS coupling of the ORRUBA silicon detector array and the GRETINA gamma ray tracking array, and a proton beam at the ATLAS facility at Argonne National Laboratory, to measure the weak (10-4) branching ratio with higher sensitivity than previous measurements.
