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arXiv · 1510.00371

Excited-state energies and scattering phase shifts from lattice QCD with the stochastic LapH method

Colin Morningstar·John Bulava·Brendan Fahy·Jacob Fallica·Andrew Hanlon·Ben Hoerz·Keisuke Juge·Chik Him Wong
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Abstract

Recent results in computing excited-state energies and meson-meson scattering phase shifts in lattice QCD are presented. A stochastic method of treating the low-lying modes of quark propagation that exploits Laplacian Heaviside quark-field smearing makes such studies possible now on large 32^3 x 256 and 48^3 x 128 lattices at near physical pion masses. Levels are identified using a variety of probe interpolating operators, which include both single-hadron and a large number of two-hadron operators.

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Colin Morningstar, John Bulava, Brendan Fahy, Jacob Fallica, Andrew Hanlon, Ben Hoerz, Keisuke Juge, Chik Him Wong. 2015-10-01. Excited-state energies and scattering phase shifts from lattice QCD with the stochastic LapH method. https://arxiv.org/abs/1510.00371

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