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arXiv · 1410.8839

Excited isovector mesons using the stochastic LapH method

Colin Morningstar·Brendan Fahy·You-Cyuan Jhang·Keisuke J. Juge·David Lenkner·Chik Him Wong
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Abstract

The spectrum of excited isovector mesons is studied using a 32^3 x 256 anisotropic lattice with u,d quark masses set to give a pion mass near 240 MeV. Results in the bosonic isovector nonstrange symmetry channels of zero total momentum are presented using correlation matrices of unprecedented size. In addition to spatially-extended single-meson operators, large numbers of two-meson operators are used, involving a wide variety of light isovector, isoscalar, and strange meson operators of varying relative momenta. All needed Wick contractions are efficiently evaluated using a stochastic method of treating the low-lying modes of quark propagation that exploits Laplacian Heaviside quark-field smearing. Level identification is discussed.

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Colin Morningstar, Brendan Fahy, You-Cyuan Jhang, Keisuke J. Juge, David Lenkner, Chik Him Wong. 2014-10-31. Excited isovector mesons using the stochastic LapH method. https://arxiv.org/abs/1410.8839

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