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تسجيل مستخدم جديدCommon Envelope Shaping of Planetary Nebulae. III. The Launching of Jets in Proto-Planetary Nebulae
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We compute successfully the launching of two magnetic winds from two circumbinary disks formed after a common envelope event. The launching is produced by the increase of magnetic pressure due to the collapse of the disks. The collapse is due to internal torques produced by a weak poloidal magnetic field. The first wind can be described as a wide jet, with an average mass-loss rate of $sim 1.3 times 10^{-7}$ Moy and a maximum radial velocity of $sim 230$ kms. The outflow has a half-opening angle of $sim 20^{circ}$. Narrow jets are also formed intermittently with velocities up to 3,000 kms, with mass-loss rates of $sim 6 times 10^{-12} $ Moy during short periods of time. The second wind can be described as a wide X-wind, with an average mass-loss rate of $sim 1.68 times 10^{-7}$ Moy and a velocity of $sim 30$ kms. A narrow jet is also formed with a velocity of 250 kms, and a mass-loss rates of $sim 10^{-12} $ Moy. The computed jets are used to provide inflow boundary conditions for simulations of proto-planetary nebulae. The wide jet evolves into a molecular collimated outflow within a few astronomical units, producing proto-planetary nebulae with bipolar, elongated shapes, whose kinetic energies reach $sim 4 times 10^{45}$ erg at 1,000 years. Similarities with observed features in W43A, OH231.8+4.2, and Hen 3-1475 are discussed. The computed wide X-wind produces proto-planetary nebulae with slower expansion velocities, with bipolar and elliptical shapes, and possible starfish type and quadrupolar morphology.
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Magnetic fields of order $10^1-10^2$ gauss that are present in the envelopes of red giant stars are ejected in common envelope scenarios. These fields could be responsible for the launching of magnetically driven winds in proto-planetary nebulae. Usi
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