摘要
We discuss the gauge dependence of physical parameter's definitions under the on-shell and the pole mass renormalization prescriptions. By two-loop-level calculations we prove for the first time that the on-shell mass renormalization prescription makes physical result gauge dependent. On the other hand, such the gauge-dependence does not appear in the result of the pole mass renormalization prescription. Our calculation also shows the gauge dependence induced by the on-shell mass renormalization prescription cannot be neglected at two-loop level.