Constraints on the Πnn Coupling Constant from the Nn System
نویسنده
چکیده
The sensitivity of the deuteron and of pp scattering to the πNN and ρNN coupling constants is investigated systematically. We find that the deuteron can be described about equally well with either large π and ρ or small π and ρ coupling constants. However, pp scattering clearly requires the strong ρ, but favors the weak π (particularly, in 3P0 at low energies). This apparent contradiction between bound-state and scattering can be resolved by either assuming charge-dependent πNN coupling constants or by adding a heavy pion to the NN model. In both cases, the neutral-pion coupling constant is small (g π /4π = 13.5).
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