Measurements are presented of short range three-particle correlations in e+e− annihilations at LEP using data collected by the DELPHI detector. At small values of the four-momentum difference, strong three-particle correlations are observed for like-sign (+++ and −−−) and for unlike-sign (++− and +−−) pion combinations which are not a consequence of two-particle correlations. A possible explanation of the observed effects in like-sign combinations is the existence of higher order Bose-Einstein interference, which significantly changes the particle distributions in jets.
Abreu, P., Cortina Gil, E., DELPHI Collaboration, & et al. (1995). Observation of short range three particle correlations in e+ e- annihilations at LEP energies. Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. https://doi.org/10.1016/0370-2693(95)00711-S