Photoproton Reactions Through Isobaric Analog States inSr88andZr90

We have measured the photoproton cross sections of ${}_{}{}^{88}{}_{}{}^{}\mathrm{Sr}$ and ${}_{}{}^{90}{}_{}{}^{}\mathrm{Zr}$ for production of ground and low-energy residual states. The results are in agreement with predictions of the particle-hole model for isobaric analog states. Strong and broad resonances are found around 21 MeV in ${}_{}{}^{88}{}_{}{}^{}\mathrm{Sr}$ and around 20 and 22 MeV in ${}_{}{}^{90}{}_{}{}^{}\mathrm{Zr}$ which agree with coherent states expected by the theory.