1998/11/16 by G. Alexander, Gideon Alexander, Alexander, Gideon +2
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Particle physics theoretical and experimental studies #hep-ph
paper · pdf · doi:10.48550/arxiv.hep-ph/9811338
16 pages, 11 figures, Based on an invited talk given by G. Alexander in the Hadron Structure '98, 7-13 Sept. 1998, Stara Lesna, Slovakia (to be published in this Conference Proceedings)
arxiv created 1998/11/16 · openalex publication_date 1998/11/16 · arxiv updated 2009/11/30 · openalex created_date 2024/04/11 · openalex updated_date 2026/07/28
This report summarises the recent studies of the Bose-Einstein Correlations (BEC) carried out by the four LEP experiments using hadronic Z0 decay events and e+ e- reactions leading to the WW decay final states. The three identical charged pion systems π± π± π± have been studied by OPAL with 4 × 106 hadronic Z0 decays events. The genuine three-pion correlations corrected for Coulomb effects, were separated from the known two-pion correlations by a novel subtraction procedure using the data events themselves. From this analysis a value of \mathrm r3 = 0.580 ± 0.029 fm was obtained. The recent L3 study of the two-dimensional two-pion BEC is also discussed. In this study, which utilised the longitudinal co-moving system, evidence is given for a non-spherical di-pion emitter shape where the ratio of the minor to major axes is found to be 0.74 ± 0.09. Next we summarise the experimental aspects of the BEC and colour reconnection phenomena in W-pair events at LEP and their contribution to the systematic error associated with the MW measurements. Finally we describe the first attempts to evaluate the ΛΛ(ΛΛ) emitter dimension via the Pauli exclusion principle with a combined result of \mathrm RΛΛ = 0.14 + 0.07-0.03 ~~\mathrm fm taup