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arXiv · 1512.07403

Generalization of the model-independent Laurent-Pietarinen single-channel pole-extraction formalism to multiple channels

Alfred Svarc·Mirza Hadzimehmedovic·Hedim Osmanovic·Jugoslav Stahov·Lothar Tiator·Ron L. Workman
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Abstract

A method to extract resonance pole information from single-channel partial-wave amplitudes based on a Laurent (Mittag-Leffler) expansion and conformal mapping techniques has recently been developed. This method has been applied to a number of reactions and provides a model-independent extraction procedure which is particularly useful in cases where a set of amplitudes is available only at descrete energies. This method has been generalized and applied to the case of a multi-channel fit, where several sets of amplitudes are analysed simultaneously. The importance of unitarity constraints is discussed. The final result provides a powerful, model-independent tool for analyzing partial-wave amplitudes of coupled or connected channels based entirely on the concepts of analyticity and unitarity.

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Alfred Svarc, Mirza Hadzimehmedovic, Hedim Osmanovic, Jugoslav Stahov, Lothar Tiator, Ron L. Workman. 2015-12-23. Generalization of the model-independent Laurent-Pietarinen single-channel pole-extraction formalism to multiple channels. https://doi.org/10.1016/j.physletb.2016.02.058

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