Structure of Light Nuclei Using Chiral Three-Nucleon Interaction.

Modern high-precision nucleon-nucleon (NN) interactions adjusted to reproduce the phase shifts in the two nucleon system need to be augmented by three-nucleon interactions (TNI) in order to reproduce properties of multi nucleon systems. Chiral perturbation theory (${\chi}PT$) at next-to-next-to-leading order (N$^2$LO) predicts three types of TNI terms. A two-pion exchange term, which is frequently used, has parameters determined from the two-nucleon ${\chi}PT$-potential and/or pion-nucleon scattering data. The other two terms, the one-pion exchange with NN-contact term and the NNN-contact term, are accompanied by undetermined low-energy constants. We include all three TNI terms in {\it ab initio} no-core shell model (NCSM) calculations. The two undetermined TNI constants are fit to binding energies of $s$-shell nuclei. The effect on the nuclear structure of adding N$^2$LO TNI is then studied in NCSM calculations for p-shell nuclei, such as $^{10,11}$B and $^{12,13}$C that are particularly sensitive to the presence of and the form of the TNI.