Vector mesons and electromagnetic form factor of the $\Lambda$ hyperon

Abstract

The measured electromagnetic form factors of $\Lambda$ hyperon in the time-like region are significantly deviated from pQCD prediction. We attribute the non-vanishing cross section near threshold to be the contribution of below-threshold $\varphi$(2170) state, supporting its exotic structure. Above the threshold, we find significant role of a wide vector meson with the mass of around 2.34 GeV, which would be the same state present in $p\bar{p}$ annihilation reactions. As a result, we give a satisfactory description of the behavior of existing data without modifying pQCD expectation.

10 pages, 1 figure, published version

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Cited by in corpus (18)

• 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 $q^2$
• The $ss\bar{s}\bar{s}$ tetraquark states and the newly observed structure $X(2239)$ by BESIII Collaboration
• Photoproduction of strange hidden-charm and hidden-bottom states
• A possible explanation of the threshold enhancement in the process $e^{+}{e}^{-}\to \Lambda \bar{\Lambda }$
• Study of the process $e^{+}{e}^{-}\to \varphi \eta$ at center-of-mass energies between 2.00 and 3.08 GeV
• Electromagnetic form factors of $\Lambda$ hyperon in the vector meson dominance model and a possible explanation of the near-threshold enhancement of the $e^{+}{e}^{-}\to \Lambda \bar{\Lambda }$ reaction
• Timelike nucleon electromagnetic form factors: All about interference of isospin amplitudes
• Electromagnetic form factors of the ${\Omega }^{-}$ baryon in the spacelike and timelike regions
• Toy model to understand oscillatory behavior in timelike nucleon form factors
• Production and decay of polarized hyperon-antihyperon pairs
• Dispersion-theoretical analysis of the electromagnetic form factors of the $\Lambda$ hyperon
• Higher strangeonium decays into light flavor baryon pairs like $\Lambda \bar{\Lambda }$, $\Sigma \bar{\Sigma }$, and $\Xi \bar{\Xi }$
• $\Lambda \bar{\Lambda }$ final-state interaction in the reactions $e^{+}{e}^{-}\to \varphi \Lambda \bar{\Lambda }$ and $e^{+}{e}^{-}\to \eta \Lambda \bar{\Lambda }$
• The electromagnetic form factors of ${\Lambda }_c$ hyperon in the vector meson dominance model
• Space-like Electromagnetic Form Factors of Lambda- and Sigma-Baryons from Quark-Diquark Faddeev Equations
• The electromagnetic form factors and spin polarization of ${\Lambda }_c^{+}$ in the process $e^{+}{e}^{-}\to {\Lambda }_c^{+}{\bar{\Lambda }}_c^{-}$