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arXiv · 0910.4595

Meson-Baryon Scattering Parameters from Lattice QCD with an Isospin Chemical Potential

Paulo F. Bedaque·Michael I. Buchoff·Brian C. Tiburzi
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Abstract

The extraction of meson-baryon scattering parameters from lattice QCD is complicated by the necessity, in some channels, of including annihilation diagrams. We consider a strategy to avoid the need for these extremely costly and noisy contributions. The strategy is based on simulations with an isospin chemical potential which, contrary to a baryon chemical potential, has no sign problem. When the isospin chemical potential is larger than a critical value, a charged pion condensate forms. Baryons propagating in the pion condensate will have their masses modified by pion-baryon scattering parameters. Consequently these parameters can be extracted from lattice QCD simulations in an isospin chemical potential, and we detail precisely which low-energy constants using baryon chiral perturbation theory.

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Paulo F. Bedaque, Michael I. Buchoff, Brian C. Tiburzi. 2009-10-23. Meson-Baryon Scattering Parameters from Lattice QCD with an Isospin Chemical Potential. https://doi.org/10.1103/physrevd.80.114501

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