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arXiv · hep-lat/0606005

Exotic Meson Decay Widths using Lattice QCD

M. S. Cook·H. R. Fiebig
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Abstract

A decay width calculation for a hybrid exotic meson h, with JPC=1-+, is presented for the channel h->pi+a1. This quenched lattice QCD simulation employs Luescher's finite box method. Operators coupling to the h and pi+a1 states are used at various levels of smearing and fuzzing, and at four quark masses. Eigenvalues of the corresponding correlation matrices yield energy spectra that determine scattering phase shifts for a discrete set of relative pi+a1 momenta. Although the phase shift data is sparse, fits to a Breit-Wigner model are attempted, resulting in a decay width of about 60 MeV when averaged over two lattice sizes.

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M. S. Cook, H. R. Fiebig. 2006-06-05. Exotic Meson Decay Widths using Lattice QCD. https://doi.org/10.1103/physrevd.74.034509

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