Test of the \boldmath{$\tau$}-Model of Bose-Einstein Correlations and Reconstruction of the Source Function in Hadronic Z-boson Decay at LEP

TL;DR

This paper tests the au-model for Bose-Einstein correlations in Z-boson decays, reconstructs the particle emission source, and explores model limitations regarding emission region elongation.

Contribution

It validates the au-model with a Lévy stable distribution and reconstructs the emission source in hadronic Z decays, identifying its limitations.

Findings

Good fit with Lévy stable distribution and au-model

Reconstructed space-time evolution of particle emission

Identified model's inability to account for emission region elongation

Abstract

Bose-Einstein correlations of pairs of identical charged pions produced in hadronic Z decays are analyzed in terms of various parametrizations. A good description is achieved using a L\'evy stable distribution in conjunction with a model where a particle's momentum is correlated with its space-time point of production, the \taumodel. Using this description and the measured rapidity and transverse momentum distributions, the space-time evolution of particle emission in two-jet events is reconstructed. However, the elongation of the particle emission region previously observed is not accommodated in the \taumodel, and this is investigated using an \adhoc/ modification.