Test of non point-like behavior of Fermions

We search in measurements from LEP, TRISTAN, CDF, D0 and UA1 for those phenomena beyond the Standard Model where the fundamental particles can exhibit non point‐like behavior. The total and differential cross sections for the reaction e+e− → γγ(γ) measured at center‐of‐mass energies from 55 GeV to 207 GeV are used for a global fit to test the hypothesis of an excited electron and contact interaction induced terms. The best value for the fit exhibits an approximately 5 σ effect for the scale factor of an excited electron of (1/Λ ± 4 ) best = −(1.11 ± 0.20) × 10 −10 GeV −4 and the scale of contact interaction of (1/Λ4) best = −(4.05 ± 0.73) × 10−13 GeV −4 but with the opposite to the expected in the modified cross section sign. An empirical scheme is discussed to encompass all fermions and bosons in one framework, if these particles would be geometrically extended objects.