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arXiv · 1506.02375

Spectral representation for u- and t-channel exchange processes in a partial-wave decomposition

M. F. M. Lutz·E. E. Kolomeitsev·C. L. Korpa
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Abstract

We study the analytic structure of partial-wave amplitudes derived from u- and t-channel exchange processes. The latter plays a crucial role in dispersion-theory approaches to coupled-channel systems that model final state interactions in QCD. A general spectral representation is established that is valid in the presence of anomalous thresholds, decaying particles or overlapping left-hand and right-hand cut structures as it occurs frequently in hadron physics. The results are exemplified at hand of ten specific processes.

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M. F. M. Lutz, E. E. Kolomeitsev, C. L. Korpa. 2015-06-08. Spectral representation for u- and t-channel exchange processes in a partial-wave decomposition. https://doi.org/10.1103/physrevd.92.016003

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