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arXiv · 0704.3167

The Goldberger-Miyazawa-Oehme sum rule revisited

V. V. Abaev·P. Metsä·M. E. Sainio
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Abstract

The Goldberger-Miyazawa-Oehme sum rule is used to extract the pion-nucleon coupling constant from experimental $π$N information. Chiral perturbation theory is exploited in relating the pionic hydrogen s-wave level shift and width results to the appropriate scattering lengths. The deduced value for the coupling is $f^2 = 0.075 \pm 0.002$, where the largest source of uncertainty is the determination of the s-wave $π^- p$ scattering length from the atomic level shift measurement.

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V. V. Abaev, P. Metsä, M. E. Sainio. 2007-05-21. The Goldberger-Miyazawa-Oehme sum rule revisited. https://doi.org/10.1140/epja/i2007-10377-6

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