Invariant-mass spectrum of $\Lambda \bar{\Lambda }$ pair in the process $e^{+}{e}^{-}\to \varphi \Lambda \bar{\Lambda }$

Abstract

We show that the final-state interaction perfectly explains the recent experimental data of BESIII Collaboration on the near-threshold invariant-mass spectrum of $\Lambda \bar{\Lambda }$ in the process $e^{+}{e}^{-}\to \varphi \Lambda \bar{\Lambda }$. The position of peak in invariant-mass spectrum is above the threshold though the interaction of $\Lambda$ and $\bar{\Lambda }$ is due to an attractive potential. This potential has a simple form and depends only on two parameters. We show that the invariant-mass spectrum is consistent with the quantum numbers $J^{PC}=1^{++}$ and $2^{++}$ of $\Lambda \bar{\Lambda }$ pair but contradicts to $J^{PC}=2^{-+}$.

arXiv comment3 pages, 1 figure

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Cited by in corpus (5)

• $N\bar{N}$ production in $e^{+}{e}^{-}$ annihilation near the threshold revisited
• Final-state interaction in the process $e^{+}{e}^{-}\to {\Lambda }_c{\bar{\Lambda }}_c$
• Natural explanation of recent results on $e^{+}{e}^{-}\to \Lambda \bar{\Lambda }$
• Near-threshold resonance in $e^{+}{e}^{-}\to {\Lambda }_c{\bar{\Lambda }}_c$ process
• $\Lambda \bar{\Lambda }$ final-state interaction in the reactions $e^{+}{e}^{-}\to \varphi \Lambda \bar{\Lambda }$ and $e^{+}{e}^{-}\to \eta \Lambda \bar{\Lambda }$