  We develop a fully spatio-temporal numerical model, based on stochastic
simulations, simulating the generation of spatio-temporal multimode spontaneous
parametric down conversion, the propagation of the signal and idler beams
through a Hong-Ou-Mandel interferometer and the detection of the outgoing beams
with two separate detectors arrays. Spatial and temporal properties of the
two-photon interference are investigated by measuring the spatial distribution
of the momenta coincidence counts between the time integrated outgoing
far-field images and a full spatio-temporal HOM dip is exhibited. Numerical
results also demonstrate that the spatio-temporal coherence properties of
bi-photon wave packets can be fully characterized with detectors arrays with no
temporal resolution.
