萝莉的烦躁期Infrared renormalons and $1/Q^2$ power corrections in deep-inelastic sum rules are studied. The renormalization of operators with power divergence are discussed. The higher-twist terms in the operator product expansion are shown to account for the residual
According to the divergence behaviors of composite operators in QCD,they can be classi?ed into three categories(I disregard operators with vanishing physical matrix elements, which include BRST-exact operators and the equations of motion operators[20]):?Finite operators:These include vector and non-singlet axial-vector currents of quarks and their divergence like¯ψmψ,the energy-momentum tensor,the angular momentum density,the topological charge density F?F,etc.These operators are associated with the symmetries of the QCD lagrangian,and are physical observables of the system.
