Charm Mass Determination from QCD Sum Rules: A Revision of the Classical Method

In this work we take a revised look at the charm quark mass determination from QCD sum rules analyses. On the theoretical side we use the most up to date calculations (amounting to up ${O(alpha_s^3)}$ expressions) and on the experimental side, to our knowledge, the most complete data set (maximum coverage of the energy spectrum). We reconsider the estimate of perturbative uncertainties (due to truncation of the series in ?? _s ) proposing four alternative methods (equivalent in perturbation theory) to determine the ${rm{overline{MS}}}$ charm quark mass. We also use a very robust method to combine data from different experiments when systematic correlated errors are mainly due to normalization. This allows to use experimental data up to 10.5GeV, and to quantify statistic and systematic experimental errors in a meaningful way.