Applications of one-loop and higher order lattice QCD perturbation theory

• Applicant: Privatdozent Dr. Arwed Schiller
• Subject Area: Nuclear and Elementary Particle Physics, Quantum Mechanics, Relativity, Fields
• Term: from 2008 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 81714033

Lattice QCD is the most successful candidate to describe the non-perturbative part of the strong interactions. Renormalization is needed to relate observables obtained from lattice QCD to the measured counterparts. Lattice perturbation theory of QCD is an essential tool to compute renormalization factors and to investigate how lattice observables depend on lattice artefacts. For the presently used improved lattice actions we plan to calculate a lot of missing one-loop quantities – moments of generalized parton distributions, matrix elements of gluon operators and higher moments of structure functions. To improve the predictability of perturbative results we additionally will use the rather new method of numerical stochastic perturbation theory and plan to compute correlation functions and their corresponding renormalization factors in higher orders. The operator product expansion is the basic theoretical tool to provide most informations for the structure of hadrons. To handle lattice artefacts in that expansion we will compute the current-current correlators for different fermion lattice formulations and plan to find the perturbative renormalization factors for the so-called Wilson coefficients.

• DFG Programme: Research Grants