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Nuclear forces with Delta-excitations up to next-to-next-to-leading order I: peripheral nucleon-nucleon waves

Hermann Krebs·Evgeny Epelbaum·Ulf-G. Meißner
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Abstract

We study the two-nucleon force at next-to-next-to-leading order in a chiral effective field theory with explicit Delta degrees of freedom. Fixing the appearing low-energy constants from a next-to-leading order calculation of pion-nucleon threshold parameters, we find an improved convergence of most peripheral nucleon-nucleon phases compared to the theory with pions and nucleons only. In the delta-full theory, the next-to-leading order corrections are dominant in most partial waves considered.

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Hermann Krebs, Evgeny Epelbaum, Ulf-G. Meißner. 2007-03-27. Nuclear forces with Delta-excitations up to next-to-next-to-leading order I: peripheral nucleon-nucleon waves. https://doi.org/10.1140/epja%2Fi2007-10372-y

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