Spectrum of few-body systems in a finite volume

Abstract

Lattice quantum chromodynamics calculations of multi-baryon systems with physical quark masses could bridge the gap between nuclear physics and its fundamental theory. Such calculations are performed on a finite grid, and thus extrapolation of finite-volume numerical results to the physical-relevant free-space quantities is needed. A common approach for the extrapolation utilizes the two-body Lüscher formula and its generalization to larger systems. To understand better the accuracy of this approach we study here two model systems, bosonic and fermionic. The few-body systems are solved with the stochastic variational method in a periodic box, and the extrapolated values are compared to those calculated directly in free space.