Triples Counting and Three-Nucleon Forces in Light Nuclei

We report Green's function Monte Carlo studies of three-nucleon forces (3NF) in light nuclei. The 3NF components studied include the two-pion $s$-wave and $p$-wave terms (both anticommutator and commutator pieces) and one-pion/short- and short-/short-range phenomenological terms. (In chiral effective field theories, these correspond to the $c_1$, $c_3$, $c_4$, $c_D$, and $c_E$ terms, respectively.) Their contributions to the energy of light ($A~\leq~10$) nuclei is broken down by total spin $S$ and isospin $T$ = 1/2 or 3/2 and both the uncorrelated and correlated distributions of these triples are counted. We also study the energy dependence on the short-range cutoffs of the 3NF component functions and examine various projections to isolate specific contributions of 3NF to halo nuclei.