Precise measurements of the proton electromagnetic form factor in the time‐like region from threshold up to Q2=4.2 (GeV/c)2

The values of the proton form factor in the time‐like region have been determined for values of Q2 ranging from threshold to 4.2 (GeV/c)2. The data were collected in an experiment performed at the LEAR at CERN. The final results are presented here. We observed a s dependence of the form factor near threshold which is not in agreement with the previous experiments. We found also the CM angular distributions of the e+e− pair at various energies compatible with the ‖Ge‖=‖Gm‖ hypothesis.