Quantum Monte Carlo calculations of excited states inA=6–8nuclei

A variational Monte Carlo method is used to generate sets of orthogonal trial functions, ${\Psi }_T(J^{\pi };T)$, for given quantum numbers in various light $p$-shell nuclei. These ${\Psi }_T$ are then used as input to Green’s function Monte Carlo (GFMC) calculations of first, second, and higher excited $(J^{\pi };T)$ states. Realistic two- and three-nucleon interactions are used. We find that if the physical excited state is reasonably narrow, the GFMC energy converges to a stable result. With the combined Argonne ${\mathrm{v}}_{18}$ two-nucleon and Illinois-2 three-nucleon interactions, the results for many second and higher states in $A=6–8$ nuclei are close to the experimental values.