Extraction of the total photabsorption cross section for 24Mg

Abstract

Accurate nuclear data is a key factor in determining the suitability and reliability of many theoretical nuclear models and large-scale calculations. One of the main components of these calculations is how nuclei respond to an electro-magnetic field. The excitation of the isovector giant dipole resonance (IVGDR) is of particular importance in both nuclear structure studies as well as being the main mode of interaction of ultra-high-energy cosmic rays with the extra-galactic medium en route to Earth. This study investigates the photoabsorption cross section in the region of the IVGDR in 24Mg through the use of proton inelastic scattering and the equivalent virtual photon method. The K600 spectrometer at the iThemba LABS facility was used to obtain high resolution, low background 24Mg(p,p’)24Mg* inelastic scattering data. The virtual photon absorption method proved effective and the photoabsorption cross section is in agreement with the broad structure of previous data using real photons and improved on the fine structure thereof.