Bose-Einstein correlations in e+e- collisions

The MARK II detector is used to study the Bose-Einstein correlation between pairs and triplets of charged pions produced in hadronic decays of the J/psi/, the √s = 4 to 7 GeV continuum above the J/psi/, two photon events at √s = 29 GeV, and e/sup /plus//e/sup /minus// annihilation events at √s = 29 GeV as a function of Q2, the four-momentum transfer squared. After corrections for Coulomb effects and pion misidentification, we find a nearly full Bose-Einstein enhancement α in the J/psi/ and the two photon data and about half the maximum value in the other two data sets. The radius parameter /tau/(an average over space and time) given by pion pair analyses lies within a band of +-0.10 fm around 0.73 fm and is the same, within errors, for all four data sets. Pion triplet analyses also give a consistent radius of ∼ 0.54 fm. fits to two-dimensional distributions R(q/sub T/2, q/sub C/2) of invariant components of Q2 = q/sub T/2 /plus/ q/sub C/2 give /tau//sub T/ ∼ /tau/C ∼ /tau/, where q/sub T/ is the transverse three-momentum difference calculated with respect to the net pair three-momentum, and q/sub C/ is in effect the longitudinal three-momentum difference in the pion pair rest frame. When q/sub T/ is calculated with respect to the jet axis for two-jet events in the e/sup /plus//e/sup /minus// annihilation data at √s = 29 GeV, a fit to R(q/sub T/2, q/sub C/2) also gives /tau//sub T/ ∼ /tau//sub C/ ∼ /tau/. Noting that q/sub L/ and q0 are not invariant, we make fits to R(/sub T//sup T/, q/sub L/2) and to R(q/sub T/2, q02) (Kopylov formulation), and we find /tau/0 ∼ /tau//sub L/ ∼ /23//tau//sub T/ to /12//tau//sub T/. 44 refs., 43 figs., 15 tabs