Monday, September 25, 2017, 1:30 PM, room 112
Chad Ummel
Understanding and Measuring Nuclear Reactions at Astrophysical Energies

The slow neutron capture process (s-process) is a series of nuclear reactions responsible for the synthesis of approximately half the atomic nuclei heavier than iron. The s-process proceeds via a series of neutron capture and beta decay reactions in the low neutron flux environment of asymptotic giant branch (AGB) stars. The primary source of neutrons for the s-process is the 13C(.FNa,n)16O reaction. Extrapolation of the 13C(alpha,n)16O S-factor into the Gamow window is complicated by the unknown influence of a one-half+ resonance in 17O near the alpha-capture threshold, prompting an international effort to directly measure the cross section at low energies. The inherent challenges of this measurement are discussed and recent results and their implications are highlighted.