Baryon masses at nonzero isospin/kaon density

Abstract

We present a lattice QCD calculation of the ground-state energy shifts of various baryons in a medium of pions or kaons at a single value of the quark mass corresponding to a pion mass of m[subscript π] ~ 390 MeV and a kaon mass of m[subscript K] ~ 540 MeV, and in a spatial volume V ~ (4 fm)[superscript 3]. All systems are created using a canonical formalism in which quark propagators are contracted into correlation functions of fixed isospin/kaon density. We study four different systems, Σ[superscript +](π[superscript +])n, Ξ[superscript 0](π[superscript +])[superscript n], p(K[superscript +])[superscript n], and n(K[superscript +])[superscript n], for up to n = 11 mesons. From the ground-state energy shifts we extract two- and three-body scattering parameters, as well as linear combinations of low-energy constants appearing in tree-level chiral perturbation theory.