D-ASTERISK RADIATIVE DECAYS AND STRONG-COUPLING OF HEAVY MESONS WITH SOFT PIONS IN A QCD RELATIVISTIC POTENTIAL MODEL

In the framework of a QCD inspired relativistic potential model, we ev aluate radiative decay rates of heavy mesons and their coupling with s oft pions. The agreement with the existing experimental data is satisf actory. In the limit m(Q) --> infinity one obtains results in agreemen t with the Heavy Quark Effective Theory and is able to predict the val ues of the relevant couplings; in particular, for the scaled BBpi str ong coupling constant g, we find that the non relativistic constituent quark model prediction g = 1 is modified, by the inclusion of the rel ativistic effects due to the light quarks, to the value g = 1/3, in ag reement with recent QCD sum rules determination.