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arXiv · 1308.5186

Baryon masses at nonzero isospin/kaon density

William Detmold·Amy N. Nicholson
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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_π~390 MeV and a kaon mass of m_K~540 MeV, and in a spatial volume V (4fm)^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^+(π^+)^n, Ξ^0(π^+)^n, p(K^+)^n, and n(K^+)^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.

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William Detmold, Amy N. Nicholson. 2013-10-15. Baryon masses at nonzero isospin/kaon density. https://doi.org/10.1103/physrevd.88.074501

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