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Numerical simulations of protostellar encounters II. Coplanar disc-disc encounters

S. J. Watkins·A. S. Bhattal·H. M. J. Boffin·N. Francis·A. P. Whitworth
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Abstract

It is expected that an average protostar will undergo at least one impulsive interaction with a neighbouring protostar whilst a large fraction of its mass is still in a massive, extended disc. Such interactions must have a significant impact upon the evolution of the protostars and their discs. We have carried out a series of simulations of coplanar encounters between two stars, each possessing a massive circumstellar disc, using an SPH code that models gravitational, hydrodynamic and viscous forces. We find that during a coplanar encounter, disc material is swept up into a shock layer between the two interacting stars, and the layer then fragments to produce new protostellar condensations. The truncated remains of the discs may subsequently fragment; and the outer regions of the discs may be thrown off to form circumbinary disc-like structures around the stars. Thus coplanar disc-disc encounters lead efficiently to the formation of multiple star systems and small-N clusters.

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S. J. Watkins, A. S. Bhattal, H. M. J. Boffin, N. Francis, A. P. Whitworth. 1998-05-28. Numerical simulations of protostellar encounters II. Coplanar disc-disc encounters. https://doi.org/10.1046/j.1365-8711.1998.01987.x

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