Observations of Energy Transport

Next: A Long-Range Perspective

Observations of Energy Transport

Alan H. Bridle

National Radio Astronomy Observatory,
520 Edgemont Road, Charlottesville, VA 22903-2475, U.S.A.

Abstract:

There is now good evidence for long-expected ingredients of the jet-launcher in nearby galaxies, and for possible miniatures of it in our galaxy. There is also now a strong case for energy transport at bulk relativistic velocities to kiloparsec scales in FR I sources, and to the hot spots in FR II sources. It therefore seems that the dynamical pictures of (outward) energy transport in FR I and FR II sources can be unified, by studying (both theoretically and observationally) how jets decelerate in elliptical galaxies. Our view of jets in lobe-dominated FR II sources may be conditioned by Doppler ``hiding", which favors the emission from their slower-moving outer layers. Some old problems in jet confinement have faded as we learned more about hypersonic jet propagation, but some old solutions may be jeopardized by recent X-ray data. Radio source environs are now understood to be dynamic, and able to bend jets without large peculiar motions of the ``engine". Some important transition scales, both across and along jets, are being identified: imaging and polarimetry of radio galaxies and quasars on these scales should help to refine models of jet acceleration, deceleration and disruption.

Observations of Energy Transport

Abstract:

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