Mass transfer in double white dwarf binaries

Juhan Frank, Louisiana State University


I review the implications of our recent numerical simulations of the hydrodynamics of Roche lobe overflow in double white dwarf binaries, with special emphasis on the stability and survival of such systems after the onset of dynamically unstable mass transfer. We find that some of these systems may survive and enter a secular phase of orbital expansion, driven by gravitational radiation, undergoing slow and decreasing mass transfer, and be observable as AM Canum Venaticorum binaries. © 2008 Elsevier B.V. All rights reserved.