Pre-Common-Envelope Mass Loss from Coalescing Binary Systems

Understand

Binary systems undergoing unstable Roche Lobe overflow spill gas into their circumbinary environment as their orbits decay toward coalescence.

• In this paper, we use a suite of hydrodynamic models of coalescing binaries involving an extended donor and a more compact accretor.
• We focus on the period of unstable Roche Lobe overflow that ends as the accretor plunges within the envelope of the donor at the onset of a common envelope phase.
• During this stage, mass is removed from the donor and flung into the circumbinary environment.