The physical mechanism(s) responsible for transitioning from a sphericalAsymptotic Giant Branch (AGB) star to an asymmetric post-AGB (pAGB) object ispoorly understood. In particular, excess momenta in the outflows of pAGBobjects suggest that a binary may be required to supply an additional source ofenergy and angular momentum. The extraction of rotational energy from theengine is likely fundamental and may be facilitated if a dynamo is operating inthe interior. In this regard, single star magnetic outflow models have beenproposed as mechanisms for producing and shaping PNe, however these modelsneglect the back-reaction of the large-scale magnetic field on the flow. Here we present a transient $\alpha-\Omega$ dynamo operating in the envelopeof an AGB star in (1) an isolated setting and (2) a common envelope in whichthe secondary is a low-mass companion in-spiraling in the AGB interior. Theback reaction of the fields on the shear is included and differential rotationand rotation deplete via turbulent dissipation and Poynting flux. For anisolated star, the shear must be resupplied in order to sufficiently sustainthe dynamo. We comment on the energy requirements that convection must satisfyto accomplish this. For the common envelope case, a robust dynamo can result asthe companion provides an additional source of energy and angular momentum.
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