Charm quark mass from QCD sum rules for the charmonium system

In this work, the charm-quark mass is obtained from a QCD sum-rule analysis of the charmonium system. In our investigation we include results from non relativistic QCD at next-to-next-to-leading order. Using the pole-mass sche me, we obtain a value of M-c = 1.70+/-0.13 GeV for the charm-pole mass. The introduction of a potential-subtracted mass leads to an improved scale dep endence. The running (MS) over bar mass is then determined to be m(c)(m(c)) = 1.23+/-0.09 GeV. (C) 2001 Published by Elsevier Science B.V.