Quantum Monte Carlo Simulations of Nuclei and Nuclear Reactions

Abstract

Nuclear Hamiltonian and Electro‐weak current operators have large spin‐isospin dependent terms dictated by the pseudoscalar‐isovector nature of pion, the carrier of long range nuclear forces. We discuss techniques developed to use variational and Green’s function Monte Carlo methods with realistic nuclear Hamiltonians and current operators. Their computing requirements increase approximately as 4A, where A is the number of nucleons in the nucleus or the reaction. With presently available computers, nuclei having up to 12 nucleons can be simulated with realistic Hamiltonians. Thus the scope of presently accessible problems in nuclear physics and astrophysics is significant. For example all primordial nuclear processes as well most of the solar nuclear reactions can be simulated. We give an overview of the many nuclear observables and low‐energy nuclear reactions of interest in astrophysics that have been studied with these methods. Finally we discuss the possibilities to eliminate the exponential, ∼ 4A, growth of computing requirements necessary to simulate larger nuclei.