We calculate two-pion correlation functions at finite rapidities based on a hydrodynamical model which does not assume explicit boost invariance along the collision axis. Extracting the HBT radii through chi2 fits in both Cartesian and Yano-Koonin-Podgoretski parametrizations, we compare them with experimental results from the PHOBOS collaboration. Based on the results, we discuss longitudinal expansion dynamics.
Hydrodynamical model; Pion interferometry; Boost invariance
