Can the Formation of X-ray Obscuring Tori and Jets in Active Galaxies be   Determined by One Parameter?
  A torus of reduced differential rotation can form in the inner $\siml 10$pc core of active galactic nuclei incurring a density enhancement that can account for obscuration of X-rays in Seyferts when the initial inner core to black hole mass ratio $\gsim 50$. The same density enhancement and reduction in differential rotation can also lead to dynamo growth of poloidal fields which attain a magnitude $\sim 10^4$G when accreted onto the central engine. As radio jet models often employ poloidal fields as agents in extracting power for the jet luminosity, we suggest that jetted AGN might require this poloidal field production. Although the poloidal field would be originally produced in the obscuring torus, jetted objects are less likely to have obscuring tori: The poloidal field would only aid in powering jet emission after it accretes with the torus matter to the central engine. Thus, only during the relatively short torus accretion time scale could there be both a jet and and torus. 
Eric G. Blackman (Institute of Astronomy, Cambridge UK), Insu Yi   (Institute for Advanced Study, Princeton, NJ)