The three-loop polarized singlet anomalous dimensions from off-shell operator matrix elements

Understand

Future high luminosity polarized deep--inelastic scattering experiments will improve both the knowledge of the spin sub--structure of the nucleons and contribute further to the precision determination of the strong coupling constant, as well as, reveal currently yet unknown higher twist contributions in the polarized sector.

• For all these tasks to be performed, it is necessary to know the QCD leading twist scaling violations of the measured structure functions.
• Here an important ingredient consists in the polarized singlet anomalous dimensions and splitting functions in QCD.
• We recalculate these quantities to three--loop order in the M--scheme by using the traditional method of space--like off--shell massless operator matrix elements, being a gauge--dependent framework.