Speaker
Description
The study of exotic, short-lived nuclei far from the valley of stability is crucial for the exploration of nuclear structure and nucleosynthesis. To fulfill these pursuits, fusion-evaporation reactions serve as an essential reaction mechanism for accessing exotic nuclei such as those near the proton drip line. However, the tools available for predicting fusion-evaporation reaction cross-sections --- and thus making accurate reaction rate predictions for new experiments --- have been found to overestimate by an order of magnitude. To address this, fusion-evaporation cross-section measurements are being made via comparison against observed gamma-ray peaks from Coulomb excitation.
This presentation will begin by introducing an experiment conducted at TRIUMF, Canada's particle accelerator centre, which used: the TRIUMF-ISAC Gamma-Ray Escape Suppressed Spectrometer (TIGRESS) for gamma-rays; the CsI Ball array in the TIGRESS Integrated Plunger (TIP) for charged particles; a calcium target with a thick gold backing; and a high-intensity stable beam of 20Ne to access the region near doubly magic 56Ni via 40Ca(20Ne,XaYp) reactions. The majority of the presentation will centre on the methodology used to measure fusion-evaporation cross-sections in the absence of a continuously-monitored beam intensity by combining the well-known Coulomb excitation formalism, theoretical fusion-evaporation angular distributions, and efficiency-corrected relative gamma-ray intensities. Results will be presented and discussed.