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arXiv · 1109.0308

Excited-State Hadron Masses from Lattice QCD

Colin Morningstar·John Bulava·Justin Foley·You-Cyuan Jhang·Keisuke Juge·David Lenkner·Chik Him Wong
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Abstract

Progress in computing the spectrum of excited baryons and mesons in lattice QCD is described. Large sets of spatially-extended hadron operators are used. The need for multi-hadron operators in addition to single-hadron operators is emphasized, necessitating the use of a new stochastic method of treating the low-lying modes of quark propagation which exploits Laplacian Heaviside quark-field smearing. A new glueball operator is tested, and computing the mixing of this glueball operator with a quark-antiquark operator and multiple two-pion operators is shown to be feasible.

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Colin Morningstar, John Bulava, Justin Foley, You-Cyuan Jhang, Keisuke Juge, David Lenkner, Chik Him Wong. 2011-09-01. Excited-State Hadron Masses from Lattice QCD. https://doi.org/10.1063/1.3700534

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