BINARY AND MULTIPLE STAR-FORMATION

From the growing observational evidence that binary/multiple star form ation occurs prior to the pre-main sequence (Mathieu, 1992), it is cle ar that any theory of star formation MUST also explain binary formatio n. This paper details two formation mechanisms for binary/multiple sta rs, which occur simultaneously with protostar formation. The protostel lar discs we form have masses 5 --> 30M., diameters 200 --> 4000 AU. T he 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 particl es per calculation and a prescribed cooling equation of state.