Bridging quantum chemistry and nuclear structure theory: Coupled-cluster calculations for closed- and open-shell nuclei

Abstract

We review basic elements of the single‐reference coupled‐cluster theory and discuss large scale ab initio calculations of ground and excited states of 15O, 16O, and 17O 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 obtain the converged results for 16O and promising preliminary results for 15O and 17O at the level of two‐body interactions. The calculated properties other than energies include matter density, 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 7 or 8 major oscillator shells, for which non‐truncated shell‐model calculations for nuclei with A = 15 17 active particles are presently not possible. We argue that the use of coupled‐cluster methods and computer algorithms developed by quantum chemists to calculate properties of nuclei is an important step toward the development of accurate and affordable many‐body theories that cross the boundaries of various physical sciences.