Extracting m-barc(Mc) and fDs,B from the pseudoscalar sum rules

I report here on the (first) direct extraction of the running charm quark mass m-barc(ν) from the D-meson sum rules, and on the implications of this result for the estimate of the leptonic decay constants fD(s). The outputs: m-barc(Mc) = (1.08 ± 0.11) GeV, fD ≅ (1.52 ± 0.16) fπ, fDs ≅ (1.75 ± 0.18)fπ and fB = (1.44 ± 0.07)fπ are in good agreement with the existing sum rule results obtained using the pole mass. In particular, the result fD ∼ fB supports early '87 sum rule results, which indicated a huge 1/m correction to the heavy quark symmetry expectation. This talk is based on the paper hep-ph/9712386 and updates the discussions given there