  We study spontaneous directionality in the bosonic amplification of atom
pairs emitted from an elongated Bose-Einstein condensate (BEC), an effect
analogous to `superradiant' emission of atom-photon pairs. Using a simplified
model, we make analytic predictions regarding directional effects for both
atom-atom and atom-photon emission. These are confirmed by numerical mean-field
simulations, demonstrating the the feasibility of nearly perfect directional
emission along the condensate axis. The dependence of the emission angle on the
pump strength for atom-atom pairs is significantly different than for
atom-photon pairs.
