Nuclear electric dipole moment in the cluster model with a triton: 7Li and 11B

We calculate the electric dipole moment (EDM) of the nuclei Li-7 and B-11 in the cluster model with alpha (He-4) and triton (H-3) clusters as degrees of freedom. The Li-7 and B-11 nuclei are treated in the two- and three-body problem, respectively, using the Gaussian expansion method, assuming the one-meson exchange P, CP-odd nuclear forces. We find that Li-7 and B-11 have larger sensitivity to the CP violation than the deuteron. It is also suggested that the EDMs of Li-7 and B-11, together with those of Li-6, Be-9 and the 1/2(1)(+) excited state of C-13, obey an approximate counting rule accounting for the EDM of the cluster and the alpha-N polarization. We show their sensitivity on the hadronic level CP violation in terms of the chiral effective-field theory and discuss their role in probing new physics beyond the standard model.