Application of Semilocal Coordinate-Space Regularized Chiral Forces to Elastic Nd Scattering and Breakup

We solve three-nucleon (3N) Faddeev equations with nucleon–nucleon (NN) and three-nucleon forces (3NF) derived consistently in the framework of chiral perturbation theory, taking the semilocal coordinate-space regularized chiral N $$^4$$ LO NN potential supplemented by the chiral N $$^2$$ LO 3NF regularized in the same way. Based on these solutions the nucleon–deuteron (Nd) elastic scattering and deuteron breakup reactions are studied. We checked that the elastic Nd scattering cross section can be used as an alternative observable to the doublet neutron–deuteron (nd) scattering length to fix, together with the $$^3$$ H binding energy, the strengths of the contact terms of the N $$^2$$ LO 3NF. We investigated the predicted 3NF effects in 3N continuum reactions putting an emphasis on the $$A_y$$ puzzle in low energy nd elastic scattering and on cross sections in the symmetrical-space-star and quasi-free-scattering breakup configurations. We found that the N $$^2$$ LO 3NF provides effects comparable to those of standard, (semi-)phenomenological $$2\pi $$ -exchange Tucson-Melbourne 3NF.