The Galactic Black Hole Accretion Disk α ω Dynamo Figure 1: The α ω dynamo in a galactic black hole accretion disk (ANIMATE ). The initial poloidal quadrupole field within the disk (Panel A) is sheared by the differential rotation within the disk, developing a strong toroidal component (Panel B). As a star passes through the disk it heats by shock and by radiation a fraction of the matter of the disk, which expands vertically and lifts a fraction of the toroidal flux within an expanding plume (Panel C). Due to the conservation of angular momentum, the expanding plume and embedded flux rotate ~ π/2 radians before the plume falls back to the disk (Panel D). (The Pulsed Jet Rotation Experiment explains the relative counter-rotation of an expanding plume in a rotating frame due to conserved angular momentum.) Reconnection allows the new poloidal flux to merge with and augment the original poloidal flux (Panel D).   Figure 2: A simplified schematic of the liquid sodium dynamo experiment, designed to mimic the accretion disk dynamo. The conducting fluid between the two cylinders is rotated differentially as stable annular rotational Couette flow. This flow shears the radial component of an external poloidal quadrupole field into a stronger toroidal field. The radial and azimuthal components of the poloidal quadrupole and toroidal fields are measured separately but simultaneously. Pulsed jets, simulating radiation-heated plumes, are driven off-axis, resembling star-disk collisions. The resistivity of the liquid sodium ensures the reconnection necessary for augmenting the poloidal flux by the rotated plume flux. About this document ... This document was generated using the LaTeX2HTML translator Version 97.1 (release) (July 13th, 1997) Copyright © 1993, 1994, 1995, 1996, 1997, Nikos Drakos, Computer Based Learning Unit, University of Leeds. This document was last updated by Kate Weatherall and Howard Beckley on 4/24/2001