An Investigation of the $^{48}$Ca($\gamma$,n) Cross Section between 9.5 and 15.3 MeV

A 2.7 g $^{48}$Ca target enriched to 92.4\% was probed using an incident $\gamma$-ray beam of $\sim$2\% energy resolution generated at the TUNL High Intensity $\gamma$-Ray Source (HI$\gamma$S). Prior to the experiment, no direct measurements had been made using a quasi-monoenergetic $\gamma$-ray beam. Cross sections for the ($\gamma$, n) reaction, normalized to the known D($\gamma$, n) reaction cross sections,\footnote{W.Jaus and W.S.Woolcock, \textit{Nucl. Phys.} \textbf{A}608 (1996) 399.} were measured to a precision of less than $\pm$6\% at 34 different energies between 9.5 and 15.3 MeV using a $^{3}$He proportional counter for neutron detection. The $\gamma$-ray energies span the region from the neutron emission threshold, across previously identified M1 strength, and up the low-energy edge of the E1 Giant Dipole Resonance. Neutron emission dominates the region though a few excited states in the daughter nucleus are populated. The experimental data will be presented as will the initial interpretation of this excitation function.