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arXiv · 1411.4804

Suppression of excited-state effects in lattice determination of nucleon electromagnetic form factors

G. M. von Hippel·S. Capitani·D. Djukanovic·J. Hua·B. Jäger·P. Junnarkar·H. B. Meyer·T. D. Rae·H. Wittig
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Abstract

We study the ability of a variety of fitting techniques to extract the ground state matrix elements of the vector current from ratios of nucleon three- and two-point functions that contain contaminations from excited states. Extending our high-statistics study of nucleon form factors, we are able to demonstrate that the treatment of excited-state contributions in conjunction with approaching the physical pion mass has a significant impact on the $Q^2$-dependence of the form factors.

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G. M. von Hippel, S. Capitani, D. Djukanovic, J. Hua, B. Jäger, P. Junnarkar, H. B. Meyer, T. D. Rae, H. Wittig. 2014-11-18. Suppression of excited-state effects in lattice determination of nucleon electromagnetic form factors. https://arxiv.org/abs/1411.4804

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