Abstract.
Bose-Einstein correlations are studied in pairs of charged pions from hadronic Z decays, collected by the ALEPH detector. The correlation function, measured using either the unlike-sign or the mixed reference sample, is studied in terms of the Lorentz-invariant four-momentum difference and its transverse, Q T, and longitudinal, Q L, components with respect to the longitudinal centre-of-mass system. Values for the correlation radii, R T and R L, are obtained from the fit of the Goldhaber parametrisation. The results indicate that the correlation radii values depend on the chosen kind of reference sample and on the two-jet purity.
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Received: 23 April 2004, Revised: 11 May 2004, Published online: 9 July 2004
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The ALEPH Collaboration. Two-dimensional analysis of Bose-Einstein correlationsin hadronic Z decays at LEP. Eur. Phys. J. C 36, 147–159 (2004). https://doi.org/10.1140/epjc/s2004-01884-3
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DOI: https://doi.org/10.1140/epjc/s2004-01884-3