The electromagnetic form factors of the $\Lambda$ in the timelike region

Understand

The reaction $e^+e^- \to \bar \Lambda \Lambda$ is investigated for energies close to the threshold.

• Specific emphasis is put on the role played by the interaction in the final $\bar \Lambda \Lambda$ system which is taken into account rigorously.
• For that interaction a variety of $\bar \Lambda \Lambda$ potential models is employed that have been constructed for the analysis of the reaction $\bar p p \to \bar \Lambda \Lambda$ in the past.
• The enhancement of the effective form factor for energies close to the $\bar \Lambda \Lambda$ threshold, seen in pertinent experiments, is reproduced.