  The two-particle momentum correlation function of a K^-p pair from
high-energy nuclear collisions is evaluated in the KbarN-piSigma-piLambda
coupled-channels framework. The effects of all coupled channels together with
the Coulomb potential and the threshold energy difference between K^-p and
Kbar0 n are treated completely for the first time. Realistic potentials based
on the chiral SU(3) dynamics are used which fit the available scattering data.
The recently measured correlation function is found to be well reproduced by
allowing variations of the source size and the relative weight of the source
function of piSigma with respect to that of KbarN. The predicted K^-p
correlation function from larger systems, which is less affected by the piSigma
source function, indicates that the investigation of its source size dependence
is useful in providing further constraints in the study of the KbarN
interaction.
