Bose-Einstein correlations in neutrino and antineutrino interactions with nucleons

Abstract

Four data sets of charged current neutrino and antineutrino interactions with neon, deuterium and hydrogen collected from BEBC and the 15 Foot Bubble Chamber are used to study the Bose-Einstein correlations between like-sign charged pions. Two forms of the parametrization for the effect are used. No substantial differences are found between the data sets obtained with neon, deuterium and hydrogen targets. The Lorentz invariant parametrization of Goldhaber gives for the radius of the pion emission region the valuer G =0.80 ±0.04±0.16 fm and for the chaoticity parameter the value ψ=0.61±0.04±0.15. Using the Kopylov-Podgoretskii parametrization yieldsr K =1.27±0.06±0.12 fm, ψ=0.58±0.03±0.12 and for the pion source lifetimec τ=0.52±0.05±0.12 fm. The Goldhaber parametrization was used to study the effect in further detail. The same emission radius and the same strength of the effect were found for particles produced in interactions on neutrons and protons. The data are compatible with a spherical shape of the pion emission region. No multiplicity or forward-backward dependences are found. No dependence of the effect on the event kinematical variables is seen.