Abstract
Perturbative QCD results in the scheme can be dramatically improved by switching to a scheme that accounts for the dominant power law dependence on the factorization scale in the operator product expansion. We introduce the “MSR scheme” which achieves this in a Lorentz and gauge invariant way and has a very simple relation to . Results in MSR depend on a cutoff parameter , in addition to the of . variations can be used to independently estimate (i.) the size of power corrections, and (ii.) higher-order perturbative corrections (much like in ). We give two examples at three-loop order, the ratio of mass splittings in the and systems, and the Ellis-Jaffe sum rule as a function of momentum transfer in deep inelastic scattering. Comparing to data, the perturbative MSR results work well even for , and power corrections are reduced compared to .
- Received 27 August 2009
DOI:https://doi.org/10.1103/PhysRevD.82.011501
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