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The Linear Sigma-Model in the 1/N-Expansion via Dynamical Boson Mappings and Applications to $ππ$-Scattering

Z. Aouissat·P. Schuck·J. Wambach
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Abstract

We present a non-perturbative method for the study of the O(N+1)-version of the linear sigma-model. Using boson-mapping techniques, in close analogy to those well-known for fermionic systems, we obtain a systematic 1/N-expansion for the Hamiltonian which is symmetry-conserving order by order. The leading order for the Hamiltonian is evaluated explicitly and we apply the method to $ππ$-scattering, in deriving the T-matrix to leading order.

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Z. Aouissat, P. Schuck, J. Wambach. 1997-10-20. The Linear Sigma-Model in the 1/N-Expansion via Dynamical Boson Mappings and Applications to $ππ$-Scattering. https://doi.org/10.1016/s0375-9474(97)00047-x

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