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arXiv · 0903.1666

Lattice chiral effective field theory with three-body interactions at next-to-next-to-leading order

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

We consider low-energy nucleons at next-to-next-to-leading order in lattice chiral effective field theory. Three-body interactions first appear at this order, and we discuss several methods for determining three-body interaction coefficients on the lattice. We compute the energy of the triton and low-energy neutron-deuteron scattering phase shifts in the spin-doublet and spin-quartet channels using Luescher's finite volume method. In the four-nucleon system we calculate the energy of the alpha particle using auxiliary fields and projection Monte Carlo.

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Evgeny Epelbaum, Hermann Krebs, Dean Lee, Ulf-G. Meißner. 2009-03-09. Lattice chiral effective field theory with three-body interactions at next-to-next-to-leading order. https://doi.org/10.1140/epja/i2009-10764-y

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