http://arxiv.org/abs/1902.03931
We conduct three-dimensional hydrodynamic simulations of the common envelope binary interaction and show that if the companion were to launch jets while interacting with the giant primary star’s envelope, the jets would remove a substantial fraction of the envelope’s gas. We use the setup and numerical code of an earlier common envelope study that did not include jets, with a 0.88Mo, 83Ro red giant star and a 0.3Mo companion. The assumption is that the companion star accretes mass via an accretion disk that is responsible for launching the jets which, in the simulations, are injected numerically. For the first time we conduct simulations that include jets as well as the gravitational energy released by the inspiraling core-companion system. We find that simulations with jets unbind approximately three times as much envelope mass than identical simulations that do not include jets, though the total fraction of unbound gas remains below 50 per cent for these particular simulations. The jets generate high velocity outflows in the polar directions, with mass loss per unit solid angle that can be as high as in the equatorial plane outflow. In simulations with jets we find a larger final orbital separation and a higher orbital eccentricity compared to identical simulations that have no jets. We also find that the compact binary at the end of the simulation receives a kick from the operation of the jets, which can displace the binary from the geometric center of a future nebula. Our results show that, if able to form, jets could play a crucial role in ejecting the envelope and in shaping the outflow.
S. Shiber, R. Iaconi, O. Marco, et. al.
Tue, 12 Feb 19
37/83
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