https://doi.org/10.1140/epja/i2007-10377-6
Regular Article - Hadron Physics
The Goldberger-Miyazawa-Oehme sum rule revisited
1
Petersburg Nuclear Physics Institute, 188300, Gatchina, Russia
2
Department of Physical Sciences, University of Helsinki, P.O. Box 64, 00014, Finland
3
Helsinki Institute of Physics, University of Helsinki, P.O. Box 64, 00014, Finland
Received:
23
April
2007
Accepted:
15
May
2007
Published online:
25
May
2007
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±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.
PACS: 13.75.Gx Pion-baryon interactions – / 14.20.Dh Protons and neutrons –
© Società Italiana di Fisica and Springer-Verlag, 2007
