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arXiv · hep-ex/9909009

Measurement of an Elongation of the Pion Source in Z Decays

L3 Collaboration
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Abstract

We measure Bose-Einstein correlations between like-sign charged pion pairs in hadronic Z decays with the L3 detector at LEP. The analysis is performed in three dimensions in the longitudinal center-of-mass system. The pion source is found to be elongated along the thrust axis with a ratio of transverse to longitudinal radius of $0.81\pm 0.02 ^{+0.03}_{-0.19}$.

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L3 Collaboration. 1999-09-04. Measurement of an Elongation of the Pion Source in Z Decays. https://doi.org/10.1016/s0370-2693(99)00662-0

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