Bose-Einstein Correlations in W+W- events at LEP2

TL;DR

This paper investigates Bose-Einstein correlations between particles produced in W+W- events at LEP2, providing evidence for inter-W correlations with a significance of 2.4 sigma.

Contribution

It presents the first analysis of inter-W Bose-Einstein correlations in W+W- events at LEP2 energies, with evidence suggesting their existence.

Findings

Indication of inter-W BEC between like-sign particles at 2.4 sigma significance.

Analysis based on 550 pb^{-1} of data from DELPHI detector.

Observed correlations contribute to understanding of particle production in W+W- events.

Abstract

Bose-Einstein correlations (BEC) between final state particles in the reaction e+e- -> W+W- -> q_1 anti-q_2 q_3 anti-q_4 have been studied. Data corresponding to a total integrated luminosity of 550 pb^{-1}, recorded by the DELPHI detector at centre-of-mass energies ranging from 189 to 209 GeV, were analysed. An indication for inter-W BEC between like-sign particles has been found at the level of 2.4 standard deviations of the combined statistical and systematic uncertainties.