Bose-Einstein Correlations in Charged Current Muon-Neutrino Interactions in the NOMAD Experiment at CERN

TL;DR

This study analyzes Bose-Einstein correlations in charged current muon-neutrino interactions at CERN, providing detailed measurements of source radii and chaoticity parameters, and examining their dependence on event characteristics.

Contribution

It offers the first detailed measurement of Bose-Einstein correlations in neutrino interactions, using multiple parametrizations and exploring source shape and dependence on event variables.

Findings

Measured source radii R_G and R_KP with uncertainties.

Observed a significant difference between transverse and longitudinal source dimensions.

Found weak dependence of correlation parameters on multiplicity and energy.

Abstract

Bose-Einstein Correlations in one and two dimensions have been studied, with high statistics, in charged current muon-neutrino interaction events collected with the NOMAD detector at CERN. In one dimension the Bose-Einstein effect has been analyzed with the Goldhaber and the Kopylov-Podgoretskii phenomenological parametrizations. The Goldhaber parametrization gives the radius of the pion emission region R_G = 1.01+/-0.05(stat)+0.09-0.06(sys) fm and for the chaoticity parameter the value lambda = 0.40+/-0.03(stat)+0.01-0.06(sys). Using the Kopylov-Podgoretskii parametrization yields R_KP = 2.07+/-0.04(stat)+0.01-0.14(sys) fm and lambda_KP = 0.29+/-0.06(stat)+0.01-0.04(sys). Different parametrizations of the long-range correlations have been also studied. The two-dimensional shape of the source has been investigated in the longitudinal co-moving frame. A significant difference between the transverse and the longitudinal dimensions is observed. The high statistics of the collected sample allowed the study of the Bose-Einstein correlations as a function of rapidity, charged particle multiplicity and hadronic energy. A weak dependence of both radius and chaoticity on multiplicity and hadronic energy is found.