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We study the axisymmetric, time-dependent hydrodynamics of rotating flows that are under the influence of supermassive black hole gravity and radiation from an accretion disk surrounding the black hole. This work is an extension of the earlier work presented by Proga, where nonrotating flows were studied. Here, we consider effects of rotation, a position-dependent radiation temperature, density at large radii, and uniform X-ray background radiation. As in the non-rotating case, the rotating flow settles into a configuration with two components (1) an equatorial inflow and (2) a bipolar inflow/outflow with the outflow leaving the system along the pole. However, with rotation the flow does not always reach a steady state. In addition, rotation reduces the outflow collimation and the outward flux of mass and kinetic energy. Moreover rotation increases the outward flux of the thermal energy and can lead to fragmentation and time-variability of the outflow. We also show that a position-dependent radiation temperature can significantly change the flow solution. In particular, the inflow in the equatorial region can be replaced by a thermally driven outflow. Generally, as it have been discussed and shown in the past, we find that self-consistently determined preheating/cooling from the quasar radiation can significantly reduce the rate at which the central BH is fed with matter. However, our results emphasize also a little appreciated feature. Namely, quasar radiation drives a non-spherical, multi-temperature and very dynamic flow. These effects become dominant for luminosities in excess of 0.01 of the Eddington luminosity.
We present the results from axisymmetric time-dependent HD calculations of gas flows which are under the influence of gravity of a black hole in quasars. We assume that the flows are non-rotating and exposed to quasar radiation. We take into account
We discuss the role that magnetic fields in low luminosity accretion flows can play in creating and maintaining a multi-phase medium, and show that small magnetically-confined clouds or filaments of dense cold gas can dramatically reprocess the `prim
Gaseous Bose-Einstein condensates (BECs) have become an important test bed for studying the dynamics of quantized vortices. In this work we use two-photon Doppler sensitive Bragg scattering to study the rotation of sodium BECs. We analyze the microsc
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