Bose-Einstein correlations in <img src="/fulltext-image.asp?format=htmlnonpaginated&src=R232830214359767_html\10052_2005_Article_BF01557618_TeX2GIFIE1.gif" border="0" alt=" $$\bar p$$ " />p annihilations at rest

Two-charged-pion correlations were studied in <img src="/fulltext-image.asp?format=htmlnonpaginated&src=R232830214359767_html\10052_2005_Article_BF01557618_TeX2GIFIE2.gif" border="0" alt=" $$\bar p$$ " />p(→2π^*2π⁻nπ⁰,n≥0) annihilations at rest with the CPLEAR detector at the Low-Energy Antiproton Ring (LEAR). A strong enhancement was found in the production of pairs of like-sign pions with a small value of the relative fourmomentumQ, with respect to pairs of unlike-sign pions. The observed enhancement was interpreted as a consequence of the Bose-Einstein symmetrization of the two-pion wave function. The data are well represented by a correlation function parametrized as a double-Gaussian; an exponential parametrization is also statistically acceptable. The value of the correlation strength is found to be >1. The high-quality large data samples together with the ability for K^± identification and final-state separation allowed the study of systematic effects impacting on theQ dependence of the correlation function and on the extracted space parameters of the pion sources.