  A method is presented for analysis of correlation function of two
non-identical particles with strong and Coulomb interactions, resonance
formation, channel coupling and spin structure. For resonance reactions we
derive a formula giving the small distance contribution to the correlation
function. The formalism is used to analyze the preliminary RHIC data on
$\pi^{\pm} \Xi^{\mp}$ correlation measurements. The $\Xi^{*}(1530)$ resonance
is successfully described. The $\pi \Xi$ source size is obtained.
