Modified Golberger-Miyazawa-Oehme Sum Rule
T.N. Pham, Tran Nguyen Truong · Physical Review Letters · 1973
A modified form of the Goldberger-Miyazawa-Oehme sum rule is given in terms of experimental quantities at finite energy. It can be used either to test dispersion relations or to determine accurately and unambiguously the pion-nucleon coupling constant in terms of the $\ensuremath{\pi}N$ scattering lengths.