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Axial-vector mesons in a relativistic point-form approach

A. Krassnigg
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Abstract

The Poincare invariant coupled-channel formalism for two-particle systems interacting via one-particle exchange, which has been developed and applied to vector mesons in Ref. [1] is applied to axial vector mesons. We thereby extend the previous study of a dynamical treatment of the Goldstone-boson exchange by comparison with the commonly used instantaneous approximation to the case of orbital angular momentum l=1. Effects in the mass shifts show more variations than for the vector-meson case. Results for the decay widths are sizable, but comparison with sparse experimental data is inconclusive.

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A. Krassnigg. 2004-12-05. Axial-vector mesons in a relativistic point-form approach. https://doi.org/10.1103/physrevc.72.028201

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