Bose-Einstein correlations in hadron-pairs from lepto-production on nuclei ranging from hydrogen to xenon

TL;DR

This study investigates Bose-Einstein correlations among like-sign charged hadrons produced in deep-inelastic electron and positron scattering across various nuclear targets, finding consistent signals regardless of target mass or photon-nucleon invariant mass.

Contribution

It provides the first comprehensive analysis of Bose-Einstein correlations across a wide range of nuclear targets in deep-inelastic scattering, using a Gaussian parametrization and correction methods.

Findings

Clear Bose-Einstein signals for all nuclei studied

No significant variation of correlations with nuclear mass

No dependence on photon-nucleon invariant mass

Abstract

Bose-Einstein correlations of like-sign charged hadrons produced in deep-inelastic electron and positron scattering are studied in the HERMES experiment using nuclear targets of $^1$H, $^2$H, $^3$He, $^4$He, N, Ne, Kr, and Xe. A Gaussian approach is used to parametrize a two-particle correlation function determined from events with at least two charged hadrons of the same sign charge. This correlation function is compared to two different empirical distributions that do not include the Bose-Einstein correlations. One distribution is derived from unlike-sign hadron pairs, and the second is derived from mixing like-sign pairs from different events. The extraction procedure used simulations incorporating the experimental setup in order to correct the results for spectrometer acceptance effects, and was tested using the distribution of unlike-sign hadron pairs. Clear signals of Bose-Einstein correlations for all target nuclei without a significant variation with the nuclear target mass are found. Also, no evidence for a dependence on the invariant mass W of the photon-nucleon system is found when the results are compared to those of previous experiments.