Coupled-cluster calculations for ground and excited states of closed- and open-shell nuclei using methods of quantum chemistry

摘要

We discuss large-scale ab initio calculations of ground and excited states of O-16 and preliminary calculations for O-15 and O-17 using coupled-cluster methods and algorithms developed in quantum chemistry. By using realistic two-body interactions and the renormalized form of the Hamiltonian obtained with a no-core G-matrix approach, we are able to obtain the. virtually converged results for O-16 and promising results for O-15 and O-17 at the level of two-body interactions. The calculated properties other than binding and excitation energies include charge radius and,charge form factor.. The relatively low costs of coupled-cluster calculations which are characterized by the low-order polynomial scaling with the system size, enable us to probe large model spaces with up to seven or eight major oscillator shells, for which nontruncated shell-model. calculations for nuclei with A = 15-17 active particles are presently not possible.