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arXiv · 1810.07788

Common explanation of the behavior of some $e^+e^-$ annihilation processes around $\sqrt s$ = 1.9 GeV

Peter Lichard
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Abstract

We show that the behavior of the excitation curves of some $e^+e^-$ annihilation processes close to the nucleon-antinucleon threshold can be explained either by the $ρ(1900)$ resonance itself or by its interference with other resonances. Besides the six-pion annihilation and the $e^+e^- \to K^+K^-π^+π^-$ and $e^+e^- \to Φπ^0$ processes, we also analyze the final states $ηπ^+ π^-$, $K^+ K^- π^+ π^- π^0$, and $K^+ K^-π^0 π^0$, the behavior of which around 1.6 GeV has not yet attracted attention. Analysis of the data on the $e^+e^- \to p \bar p$ and $e^+e^- \to n \bar n$ reactions clearly shows that the $ρ(1900)$ resides above the $n \bar n$ threshold.

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Peter Lichard. 2019-01-09. Common explanation of the behavior of some $e^+e^-$ annihilation processes around $\sqrt s$ = 1.9 GeV. https://doi.org/10.1103/physrevd.98.113011

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