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arXiv · hep-ph/0001203

The Nucleon Sigma Term from Threshold Parameters

M. G. Olsson
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Abstract

A new sum rule determines the nucleon sigma term by the πN elastic scattering threshold parameters alone. This "threshold" value of σ(2μ^2) provides an independent check of existing values obtained from global dispersive analyses, and also provides a realistic error assignment. Employing a recent analysis of low energy (T_π< 100 MeV) πN data our sum rule implies σ(2μ^2) = 71\pm 9 MeV.

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M. G. Olsson. 2000-04-17. The Nucleon Sigma Term from Threshold Parameters. https://doi.org/10.1016/s0370-2693(00)00505-0

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