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arXiv · 0809.3186

Renormalization of chiral two-pion exchange NN interactions with Delta-excitations: Central Phases and the Deuteron

M. Pavon Valderrama·E. Ruiz Arriola
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Abstract

The renormalization of the chiral np interaction with Delta-excitations in intermediate states is considered at next-to-leading order (NLO) and next-to-next-to-leading order (N2LO) for central waves. The inclusion of the Delta-excitation as an explicit degree of freedom improves the convergence properties of the effective field theory results for np scattering with respect to Delta-less theory, and allows the existence of a deuteron bound state in the infinite cut-off limit. The 1S_0 singlet and 3S_1 triplet phase shifts reproduce data for p ~ m_pi. The role of spectral function regularization is also discussed.

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M. Pavon Valderrama, E. Ruiz Arriola. 2009-01-28. Renormalization of chiral two-pion exchange NN interactions with Delta-excitations: Central Phases and the Deuteron. https://doi.org/10.1103/physrevc.79.044001

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