The electromagnetic form factors of $\Lambda$ hyperon in $e^{+}{e}^{-}\to \bar{\Lambda }\Lambda$

Abstract

We study the electromagnetic form factors of $\Lambda$ hyperon in the timelike region using the recent experimental data in the exclusive production of $\bar{\Lambda }\Lambda$ pair in electron-position annihilation. We present a pQCD inspired parametrization of $G_E(s)$ and $G_M(s)$ with only two parameters, and we consider a suppression mechanism of the electric form factor $G_E(s)$ compared to the magnetic form factor $G_M(s)$. The parameters are determined through fitting our parametrization to the effective form factor data in the reaction $e^{+}{e}^{-}\to \bar{\Lambda }\Lambda$. Except the threshold region, our parametrization can reproduce satisfactorily the known behavior of the existing data from the BarBar, DM2 and BESIII Collaborations. We also predict the double spin polarization observables $A_{xx}$, $A_{yy}$ and $A_{zz}$ in $e^{+}{e}^{-}\to \bar{\Lambda }\Lambda$.

5 pages, 3 figures

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Cited by in corpus (4)

• The electromagnetic form factors of $\Lambda$ hyperon in the vector meson dominance model
• Hyperon electromagnetic form factors in the timelike region
• Hyperon electromagnetic timelike elastic form factors at large $q^2$
• Vector mesons and electromagnetic form factor of the $\Lambda$ hyperon