Phenomenological local potentials for pi(-)+C-12 scattering from 120 to 766 MeV

Pion-nucleus scattering cross sections are calculated by solving a Schrodin ger equation reduced from the Klein-Gordon equation. Local potentials are a ssumed, and phenomenological potential parameters are searched energy-depen dently for a pi(-) + C-12 system so as to reproduce not only elastic differ ential cross sections but also total elastic, reaction and total cross sect ions at 13 pion incident energies from 120 to 766 MeV. The real and imagina ry parts of the local potentials thus obtained are shown to satisfy the dis persion relation. The imaginary part of the potentials as a function of the pion energy is found to peak near the Delta(1232)-resonance energy. The st rong absorption radius of the pion projectile with incident energies near t he Delta-resonance region is found to be about 1.6A(1/3) fm, which is consi stent with previous studies of the region where the decay of the Delta take s place in nuclei. The phenomenological local potentials are then compared with the local potentials exactly phase-shift equivalent to Kisslinger pote ntials for pion energies near;the Delta-resonance.