Determination of decouplet baryon magnetic moments from QCD sum rules

A complete set of QCD sum rules for the magnetic moments of decuplet baryons are derived using the external field method. They are analyzed thoroughly using a Monte Carlo based procedure. Valid sum rules are identified under the criteria of OPE convergence and ground state dominance and their predictions are obtained. The performances of these sum rules are further compared and a favorable sum rule is designated for each member. Correlations between the input and the output parameters are examined and large sensitivities to the quark condensate magnetic susceptibility chi are found. Using realistic estimates of the QCD input parameters, the uncertainties on the magnetic moments are found relatively large and they can be attributed mostly to the poorly known chi. It is shown that the accuracy can be improved to the 30% level, provided the uncertainties in the QCD input parameters can be determined to the 10% level. The computed magnetic moments are consistent with existing data. Comparisons with other calculations are made.