Effective parameters representing a density-dependent pion–nucleus potential

We have shown that the s-wave pion–nucleus potential with medium-modified density-dependent parameters, such as b0(ρ) and b1(ρ), can be represented by a conventional form with constant parameters by replacing the nuclear density (ρ(r)) with an effective density, ρe≈0.60 ρ(0). The parameters in the conventional Ericson–Ericson potential are thus interpreted as being effective ones containing density-dependent effects.