MuSIC@Indiana: an Effective Tool for Accurate Measurement of Fusion with Low-Intensity Radioactive Beams

The design, construction, and characterization of the Multi-Sampling Ionization Chamber, MuSIC@Indiana, are described. This detector provides efficient and accurate measurement of the fusion cross-section at near-barrier energies. The response of the detector to low-intensity beams of ^17,18O, ^19F, ^23Na, ^24,26Mg, ^27Al, and ^28Si at E_lab = 50-60 MeV was examined. MuSIC@Indiana was commissioned by measuring the ^18O+^12C fusion excitation function for 11 < E_cm < 20 MeV using CH_4 gas. A simple, effective analysis cleanly distinguishes proton capture and two-body scattering events from fusion on carbon. With MuSIC@Indiana, measurement of 15 points on the excitation function for a single incident beam energy is achieved. The resulting excitation function is shown to be in good agreement with literature data