A companion star launching jets in the wind acceleration zone of a giant star. (arXiv:1912.04662v1 [astro-ph.SR])
<a href="http://arxiv.org/find/astro-ph/1/au:+Hillel_S/0/1/0/all/0/1">Shlomi Hillel</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Schreier_R/0/1/0/all/0/1">Ron Schreier</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Soker_N/0/1/0/all/0/1">Noam Soker</a> (Technion, Israel)
By conducting three-dimensional (3D) hydrodynamical simulations we find that
jets that a main sequence companion launches as it orbits inside the wind
acceleration zone of an asymptotic giant branch (AGB) star can efficiently
remove mass from that zone. We assume that during the intensive wind phase a
large fraction of the gas in the acceleration zone does not reach the escape
velocity. Therefore, in the numerical simulations we blow the wind with a
velocity just below the escape velocity. We assume that a main sequence
companion accretes mass from the slow wind via an accretion disk, and launches
two opposite jets perpendicular to the equatorial plane. This novel flow
interaction shows that by launching jets a companion outside a giant star, but
close enough to be in the acceleration zone of a slow intensive wind, can
enhance the mass loss rate from the giant by ejecting some gas that would
otherwise fall back onto the giant star. The jets are bent inside the wind
acceleration zone and eject mass in a belt on the two sides of the equatorial
plane. The jet-wind interaction contains instabilities that mix shocked jets’
gas with the wind, leading to energy transfer from the jets to the wind. As
well, our new simulations add to the rich variety of jet-induced outflow
morphologies from evolved stars.
By conducting three-dimensional (3D) hydrodynamical simulations we find that
jets that a main sequence companion launches as it orbits inside the wind
acceleration zone of an asymptotic giant branch (AGB) star can efficiently
remove mass from that zone. We assume that during the intensive wind phase a
large fraction of the gas in the acceleration zone does not reach the escape
velocity. Therefore, in the numerical simulations we blow the wind with a
velocity just below the escape velocity. We assume that a main sequence
companion accretes mass from the slow wind via an accretion disk, and launches
two opposite jets perpendicular to the equatorial plane. This novel flow
interaction shows that by launching jets a companion outside a giant star, but
close enough to be in the acceleration zone of a slow intensive wind, can
enhance the mass loss rate from the giant by ejecting some gas that would
otherwise fall back onto the giant star. The jets are bent inside the wind
acceleration zone and eject mass in a belt on the two sides of the equatorial
plane. The jet-wind interaction contains instabilities that mix shocked jets’
gas with the wind, leading to energy transfer from the jets to the wind. As
well, our new simulations add to the rich variety of jet-induced outflow
morphologies from evolved stars.
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