The Dirac distorted wave impulse approximation revisited

Recently, we have proposed a new interpretation of the successful Dirac approach to protonnucleus elastic scattering, based on relativistic kinematics and the Lorentz-Lorenz correction. Here, we show that the Dirac distorted wave impulse approximation for low-lying collective states can be understood along the same lines. This confirms our view that relativistic effects are not the only possible explanation of the polarization data at intermediate energies.