Bose-Einstein correlations in the hadronic decays of the Z0

Abstract Bose-Einstein correlation between pairs of like-sign charged particles produced in e + e − annihilations near the Z 0 peak have been studied using data taken with the DELPHI detector at LEP. An enhancement is found in the production of pairs of identical pions of similar moments, with respect to a reference sample. Under the hypothesis that the pions are emitted by a spherically symmetrical source with gaussian density, the data indicate a radius of the source of r = 0.62±0.04(stat.)±0.20(syst.) fm. The large systematic uncertainty reflects the sensitivity of r to the choice of the reference sample.