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arXiv · 1506.02282

New structures in the proton-antiproton system

I. T. Lorenz·H. -W. Hammer·U. -G. Meißner
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Abstract

In the most recent measurements of the reaction $e^+e^- \rightarrow p\bar{p}$ by the BABAR collaboration, new structures have been found with unknown origin. We examine a possible relation of the most distinct peak to the recently observed $\Phi(2170)$. Alternatively, we analyse possible explanations due to the nucleon$\,\bar{\Delta}$ and $\Delta\bar{\Delta}$ thresholds. The latter could explain a periodicity found in the data.

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I. T. Lorenz, H. -W. Hammer, U. -G. Meißner. 2015-06-07. New structures in the proton-antiproton system. https://doi.org/10.1103/physrevd.92.034018

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