Wigner symmetry in the limit of large scattering lengths
نویسندگان
چکیده
We note that in the limit where the NN S0 and S1 scattering lengths, a (S0) and a 3S1), go to infinity, the leading terms in the effective field theory for strong NN interactions are invariant under Wigner’s SU(4) spin-isospin symmetry. This explains why the leading effects of radiation pions on the S-wave NN scattering amplitudes vanish as a S0) and a S1) go to infinity. The implications of Wigner symmetry for NN → NN axion and γ d→ n p are also considered.
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