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arXiv · hep-lat/0509028

Hybrid Exotic Meson Decay Width

M. S. Cook·H. R. Fiebig
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Abstract

We present results of a decay width calculation for a hybrid exotic meson(h, JPC=1-+) in the decay channel h to pi+a1. This calculation uses quenched lattice QCD and Luescher's finite box method. Operators for the h and pi+a1 states are used in a correlation matrix which was expanded by varying the smearing and fuzzing levels at source and sink points. Scattering phase shifts for a discrete set of relative pi+a1 momenta are determined using eigenvalues of the correlation matrix and formulae derived by Luescher. The phase shift data is very sparse, but fits to a Breit-Wigner model are made, resulting in a decay width of about 80 MeV.

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M. S. Cook, H. R. Fiebig. 2005-09-12. Hybrid Exotic Meson Decay Width. https://arxiv.org/abs/hep-lat/0509028

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