WEAK DECAY CONSTANTS OF LIGHT AND HEAVY PSEUDOSCALAR MESONS

We investigate the weak leptonic decays of light and heavy pseudoscala r mesons in a relativistic quark model of independent quarks. We perfo rm a static calculation of the decay constant f(M) purely on grounds o f simplicity. In order to minimize the possible uncertainty in the sta tic calculation, we estimate the ratios of the decay constants which a re found to be in good agreement, in the heavy flavor sector, with the predictions of other models available in the literature and existing experimental data. However, there is a noticeable discrepancy in the c urrent prediction for pion decay constant which demonstrates the inher ent limitations of the static approximation in the study of non-strang e light mesons.