AAS Meeting #193 - Austin, Texas, January 1999
Session 110. Jets in Quasars and Radio Galaxies
Oral, Saturday, January 9, 1999, 10:00-11:30am, Ballroom B

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[110.05] 3-D Relativistic MHD Simulations

K.-I. Nishikaw, J. Frank, D. M. Christodoulou (LSU), S. Koide, J.-I. Sakai (Toyama Univ.), H. Sol (Obs. de Paris-Meudon), R. L. Mutel (Univ. of Iowa)

We present 3-D numerical simulations of moderately hot, supersonic jets propagating initially along or obliquely to the field lines of a denser magnetized background medium with Lorentz factors of W=4.56 and evolving in a four-dimensional spacetime. The new results are understood as follows: Relativistic simulations have consistently shown that these jets are effectively heavy and so they do not suffer substantial momentum losses and are not decelerated as efficiently as their nonrelativistic counterparts. In addition, the ambient magnetic field, however strong, can be pushed aside with relative ease by the beam, provided that the degrees of freedom associated with all three spatial dimensions are followed self-consistently in the simulations. This effect is analogous to pushing Japanese ``noren'' or vertical Venetian blinds out of the way while the slats are allowed to bend in 3-D space rather than as a 2-D slab structure. We also simulate jets with the more realistic initial conditions for injecting jets for helical mangetic field, perturbed density, velocity, and internal energy, which are supposed to be caused in the process of jet generation. Three possible explanations for the observed variability are (i) tidal disruption of a star falling into the black hole, (ii) instabilities in the relativistic accretion disk, and (iii) jet-related PRocesses. New results will be reported at the meeting.

The author(s) of this abstract have provided an email address for comments about the abstract: kenichi@rouge.phys.lsu.edu

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