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The near-threshold $e^+e^- to Lambdabar{Lambda}$ reaction is studied with the assumption that the production mechanism is due to a near-$Lambda bar{Lambda}$-threshold resonance. The cross section of $e^+e^- to Lambdabar{Lambda}$ reaction is parametrized in terms of the electromagnetic form factors of $Lambda$ hyperon, which are obtained within the vector meson dominance model. It is shown that the contribution to the $e^+e^- to Lambdabar{Lambda}$ reaction from a new narrow state with quantum numbers $J^{PC}=1^{--}$ is dominant for energies very close to threshold. The mass of this new state is about 2232 MeV, which is very close to the mass threshold of $Lambda bar{Lambda}$, while its width is just a few MeV. This solves the problem that all previous calculations seriously underestimate the near-threshold total cross section of the $e^+e^- to Lambdabar{Lambda}$ reaction.
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 $phi$(2170) s
Using dispersion theory the low-energy electromagnetic form factors for the transition of a Sigma to a Lambda hyperon are related to the pion vector form factor. The additionally required input, i.e. the two-pion--Sigma--Lambda amplitudes are determi
Unexpected features of the BaBar data on e+e- in baryon-antibaryon cross sections are discussed. These data have been collected, with unprecedented accuracy, by means of the initial state radiation technique, which is particularly suitable in giving
The process $e^+ e^- to phi Lambda bar{Lambda}$ is studied using data samples collected with the BESIII detector at the BEPCII collider at center-of-mass energies $sqrt{s}$ ranging from $3.51$ to $4.60~{rm GeV}$ . An intermediate resonance structure
The process $e^{+}e^{-}rightarrowLambdabar{Lambda}$ is studied using data samples at $sqrt{s}=2.2324$, 2.400, 2.800 and 3.080 GeV collected with the BESIII detector operating at the BEPCII collider. The Born cross section is measured at $sqrt{s}$=2.2