Binary and multiple star formation

From the growing observational evidence that binary / multiple star formation occurs prior to the pre-main sequence (Mathieu, 1992), it is clear that any theory of star formation MUST also explain binary formation. This paper details two formation mechanisms for binary / multiple stars, which occur simultaneously with protostar formation. The protostellar discs we form have masses 5 30M , diameters 200 4000 AU. The binaries / multiples have separations 400 7500 AU. The formation mechanisms were found by conducting numerical simulations of two cloud collisions, using SPH and Treecode gravity with up to 200,000 particles per calculation and a prescribed cooling equation of state.