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arXiv · 0812.3653

Ground state energy of dilute neutron matter at next-to-leading order in lattice chiral effective field theory

Evgeny Epelbaum·Hermann Krebs·Dean Lee·Ulf-G. Meißner
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Abstract

We present lattice calculations for the ground state energy of dilute neutron matter at next-to-leading order in chiral effective field theory. This study follows a series of recent papers on low-energy nuclear physics using chiral effective field theory on the lattice. In this work we introduce an improved spin- and isospin-projected leading-order action which allows for a perturbative treatment of corrections at next-to-leading order and smaller estimated errors. Using auxiliary fields and Euclidean-time projection Monte Carlo, we compute the ground state of 8, 12, and 16 neutrons in a periodic cube, covering a density range from 2% to 10% of normal nuclear density.

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Evgeny Epelbaum, Hermann Krebs, Dean Lee, Ulf-G. Meißner. 2008-12-18. Ground state energy of dilute neutron matter at next-to-leading order in lattice chiral effective field theory. https://doi.org/10.1140/epja/i2009-10755-0

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