Demonstration of the auxiliary-field Monte Carlo approach for sd-shell nuclei

We apply the auxiliary-field Monte Carlo approach to the nuclear shell model in the 1s-0d configuration space. The Hamiltonian was chosen to have isovector pairing and isoscalar multipole-multipole interactions, and the calculations were performed within the fixed-particle, canonical ensemble. The results demonstrate the feasibility of the method for N≠Z even-even and odd-odd N=Z nuclei. In particular, static observables for even-even Ne isotopes and ²²Na compare well with results obtained from exact diagonalization of the Hamiltonian. Response functions are presented for ²²Ne and compared with exact results, and the viability of cranked calculations for N≠Z even-even nuclei is addressed. We present methods for computing observables in the canonical ensemble using Fourier extraction, and for determining the nucelar shape.