Quantum Monte Carlo calculations of A=9,10 nuclei -: art. no. 044310

We report on quantum Monte Carlo calculations of the ground and low-lying excited states of A=9,10 nuclei using realistic Hamiltonians containing the Argonne v(18) two-nucleon potential alone or with one of several three-nucleon potentials, including Urbana IX and three of the new Illinois models. The calculations begin with correlated many-body wave functions that have an alpha-like core and multiple p-shell nucleons, LS-coupled to the appropriate (J(pi);T) quantum numbers for the state of interest. After optimization, these variational trial functions are used as input to a Green's function Monte Carlo calculation of the energy, using a constrained path algorithm. We find that the Hamiltonians that include Illinois three-nucleon potentials reproduce ten states in Li-9, Be-9, Be-10, and B-10 with an rms deviation as little as 900 keV. In particular, we obtain the correct 3(+) ground state for B-10, whereas the Argonne v(18) alone or with Urbana IX predicts a 1(+) ground state. In addition, we calculate isovector and isotensor energy differences, electromagnetic moments, and one- and two-body density distributions.