2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/180815We 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.16 pages, 10 figuresNuclear Theorytext