E1 andE2/E0 form factors and strength distributions fromSi28(e,ep) andSi28(e,eα) coincidence scattering

Abstract
A model-independent multipole analysis of Si28(e,e’p) and Si28(e,e’α) coincidence data, taken at three momentum transfers 0.39<q<0.68 fm1, yields both E1 and E2/E0 form factors and the respective multipole strength distributions in the giant-resonance region of Si28 (Ex=14–22 MeV). While the deduced E1 strength agrees well with previous results, the total extracted E2/E0 strength is about twice the value found with isoscalar projectiles indicating the presence of large isovector E2/E0 contributions in the region of the isoscalar E2/E0 giant resonances.