Other
Scientific paper
Jan 2012
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2012aas...21932701w&link_type=abstract
American Astronomical Society, AAS Meeting #219, #327.01
Other
Scientific paper
In previous work we argued that jets might not be produced through magnetocentrifugal acceleration, but rather through the toroidal stresses of magnetorotational instability (MRI)-driven turbulent magnetohydrodynamic (MHD) accretion in a geometrically thick disk or flow. High accretion-rate protostars are among the best candidates for this process because a geometrically thick accretion disk that extends down to the central star is more plausible in this context than in other protostellar systems. These systems are also cleaner objects to study than active galactic nuclei (AGN), microquasars, and the like, which necessarily involve more exotic relativistic physics.
Here we present a novel in-depth analysis of the laboratory analog that inspired our work on this topic. This analog consists of the meridional flow around a rotating sphere in a viscoelastic fluid. We examine in detail the fluxes of mass, angular momentum, linear momentum, and energy, and how these depend upon system parameters. We find that the presence of an axial outflow depends critically upon the ratio of the analogous turbulent magnetic stress to turbulent Reynolds stress, which must be roughly equal to or larger than unity to drive an outflow. We also find that the flux of angular momentum can actually be opposed to the flow of matter within the outflow, despite the fact that the outflow is ultimately powered by the radial transport of angular momentum from the central object. In particular we show that, in contrast with magnetocentrifugal acceleration, the angular momentum of the outflow actually decreases even while the material is being axially accelerated. This translates to observational tests in protostellar jets.
There are some obvious enormous differences between compressible flow in a gravitational field and incompressible flow in a laboratory. We address this and we and argue why, despite these differences, there is much to learn from this laboratory system.
No associations
LandOfFree
Outflows from Thick, Turbulent Accretion in High Accretion-Rate Protostellar Systems does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Outflows from Thick, Turbulent Accretion in High Accretion-Rate Protostellar Systems, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Outflows from Thick, Turbulent Accretion in High Accretion-Rate Protostellar Systems will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1580221