Giant electric resonances in /sup 58/Ni studied by alpha particle capture

The reaction /sup 54/Fe(..cap alpha..,..gamma../sub 0/)/sup 58/Ni has been studied for 7.6 > or = E/sub b/MeV. Seventeen angular distributions have been measured in this energy region making it possible to separate the E2 strength from the E1 strength. The E1 cross section reaches a maximum at about the expected energy. A compact E2 resonance was observed which agrees quite well with the one measured by inelastic ..cap alpha.. scattering, with a peak cross section at about 16 MeV and a width of approx.3 MeV(half width at half maximum). The observed E1 strength equals 0.9% of the isospin allowed E1 sum rule. The measured E2 strength, however, equals 4.3% of the isoscalar E2 sum rule, which is about the same as the fraction of the total E1 strength in /sup 58/Ni excited by proton capture. Assuming only statistical processes and applying the Hauser-Feshbach formula to calculate the total ..gamma.. absorption from the measured particle-capture cross sections leads to the conclusion that the (..cap alpha..,..gamma..) reaction exciting the isoscalar giant quadrupole resonance and the (p,..gamma..) reaction exciting the giant dipole resonance must have direct components.