Total hadronic photoabsorption on nuclei in the energy range 0.5-2.6 GeV

The total photohadronic cross section measured at Bonn between 0.5 and 2.6 GeV on C, Al, Cu, Sn and Pb, has revealed also in the region 1-2 GeV a significant reduction of the photoabsorption strength on the bound nucleon compared to the free nucleon case. In this region the strength reduction decreases with the nuclear density and in the framework of a VMD inspired model can be interpreted as a signature of a low energy onset of the shadowing effect. The latter has been described in term of properties (width, mass and cross section) of vector-mesons in the nuclear medium