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arXiv · 2007.04161

Unitary ambiguity of NN contact interactions and the 3N force

L. Girlanda·A. Kievsky·L. E. Marcucci·M. Viviani
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Abstract

We identify a redundancy between two- and three-nucleon contact interactions at the fourth and fifth order of the chiral expansion respectively. In particular we show that tensor-type and spin-orbit three-nucleon contact interactions effectively account for that part of the two-nucleon interaction which depends on the total center-of-mass momentum and is unconstrained by relativity. This might give the chiral effective field theory enough flexibility to successfully address $A=3$ scattering observables already at N3LO.

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L. Girlanda, A. Kievsky, L. E. Marcucci, M. Viviani. 2020-11-10. Unitary ambiguity of NN contact interactions and the 3N force. https://doi.org/10.1103/physrevc.102.064003

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