Two-dimensional analysis of Bose-Einstein correlationsin hadronic Z decays at LEP

  • The ALEPH Collaboration
experimental physics


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.


Correlation Function Reference Sample Charged Pion Correlation Radius Mixed Reference 
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© Springer-Verlag Berlin/Heidelberg 2004

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  • The ALEPH Collaboration

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