Eur. Phys. J. A (2015) 51: 92
https://doi.org/10.1140/epja/i2015-15092-1

Regular Article - Theoretical Physics

Nuclear lattice simulations using symmetry-sign extrapolation

¹ Institute for Advanced Simulation, Institut für Kernphysik, and Jülich Center for Hadron Physics, Forschungszentrum Jülich, D-52425, Jülich, Germany
² Department of Physics, North Carolina State University, 27695, Raleigh, NC, USA
³ Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universität Bonn, D-53115, Bonn, Germany
⁴ JARA - High Performance Computing, Forschungszentrum Jülich, D-52425, Jülich, Germany
⁵ Institut für Theoretische Physik II, Ruhr-Universität Bochum, D-44870, Bochum, Germany
⁶ Department of Physics and Astronomy, Mississippi State University, 39762, Mississippi State, MS, USA

^* e-mail: t.laehde@fz-juelich.de

Received: 6 March 2015
Revised: 29 June 2015
Accepted: 5 July 2015
Published online: 30 July 2015

Abstract

Projection Monte Carlo calculations of lattice Chiral Effective Field Theory suffer from sign oscillations to a varying degree dependent on the number of protons and neutrons. Hence, such studies have hitherto been concentrated on nuclei with equal numbers of protons and neutrons, and especially on the alpha nuclei where the sign oscillations are smallest. Here, we introduce the “symmetry-sign extrapolation” method, which allows us to use the approximate Wigner SU(4) symmetry of the nuclear interaction to systematically extend the Projection Monte Carlo calculations to nuclear systems where the sign problem is severe. We benchmark this method by calculating the ground-state energies of the ¹²C, ⁶He and ⁶Be nuclei, and discuss its potential for studies of neutron-rich halo nuclei and asymmetric nuclear matter.