arXiv 1102.37352011-02-22hep-latnucl-th

Chiral effective field theory beyond the power-counting regime

Jonathan M. M. Hall, Derek B. Leinweber, Ross D. Young

备注：: 6 pages, 4 figures, conference
DOI：: 10.1063/1.3587589

英文摘要：

Novel techniques are presented, which identify the chiral power-counting regime (PCR), and realize the existence of an intrinsic energy scale embedded in lattice QCD results that extend outside the PCR. The nucleon mass is considered as a benchmark for illustrating this new approach. Using finite-range regularization, an optimal regularization scale can be extracted from lattice simulation results by analyzing the renormalization of the low energy coefficients. The optimal scale allows a description of lattice simulation results that extend beyond the PCR by quantifying and thus handling any scheme-dependence. Preliminary results for the nucleon magnetic moment are also examined, and a consistent optimal regularization scale is obtained. This indicates the existence of an intrinsic scale corresponding to the finite size of the source of the pion cloud.

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