AXIAL-CHARGE TRANSITIONS - RELATIVISTIC STUDY OF ONE-BODY AND 2-BODY CONTRIBUTIONS

Two recent experiments which isolate the axial charge, both in the nuclear medium and in free space, appear to necessitate the presence of heavy scalar mesons. In this contribution we present both experiments and their possible explanation. Heavy scalar mesons are a feature of relativistic models. In the framework of quantum hadrodynamics we analyze the one-body contribution, the response of the core and the effects due to meson exchange currents for the experiment with medium dependence.