We examine some properties of supermultiplet consisting of the U(1)_{J}
current, extended supercurrents, energy-momentum tensor and the central charge
in N=2 supersymmetric Yang-Mills theory. The superconformal improvement
requires adding another supermultiplet beginning with the U(1)_{R} current. We
determine the anomalous (quantum mechanical) supersymmetry transformation
associated with the central charge and the energy-momentum tensor to one-loop
order.Comment: 8 pages, LaTe