Hostname: page-component-cd9895bd7-q99xh Total loading time: 0 Render date: 2024-12-24T16:40:45.976Z Has data issue: false hasContentIssue false

Kinematics of kiloparsec-scale jets

Published online by Cambridge University Press:  24 March 2015

R. A. Laing
Affiliation:
ESO, Karl-Schwarzschild-Straße 2, D-85748 Garching-bei-München, Germany email: [email protected]
A. H. Bridle
Affiliation:
NRAO, 520 Edgemont Road, Charlottesville, VA 22903-2475, USA email: [email protected]
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

It has long been known that kiloparsec-scale jets in radio galaxies can be divided into two flavours: strong (found in powerful sources, narrow and terminating in compact hot-spots) and weak (found in low-luminosity sources, flaring, unable to form hot-spots and terminating in diffuse lobes or tails). Both flavours are initially relativistic, but weak jets decelerate to sub-relativistic, transonic speeds by entraining external gas while strong jets remain relativistic and supersonic until they terminate. Much is now known about the kinematics of weak-flavour jets, which can be modelled as intrinsically symmetrical, decelerating relativistic flows, and we summarize the results of our work in this area. Strong-flavour jets are relatively faint and narrow, so it has hitherto proved difficult to obtain the necessary deep, transverse-resolved images in total intensity and linear polarization. The spectacular jets in the radio galaxy NGC 6251 appear to represent a transition case between weak and strong flavours: the jets show no clear evidence for deceleration, but are relatively wide. VLA observations hint at transverse velocity structure with a very fast (Lorentz factor >5) spine surrounded by a slower shear layer. New observations with the upgraded VLA should be able to test this picture.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2015 

References

Bridle, A. H. 1984, AJ, 89, 979Google Scholar
Celotti, A., Ghisellini, G. & Chiaberge, M. 2001, MNRAS, 321, L1CrossRefGoogle Scholar
Fanaroff, B. L. & Riley, J. M. 1974, MNRAS, 167, 31PCrossRefGoogle Scholar
Jones, D. L., et al. 1986, ApJ, 305, 684Google Scholar
Laing, R. A. 1988, Nature, 331, 149Google Scholar
Laing, R. A. & Bridle, A. H. 2002a, MNRAS, 336, 328Google Scholar
Laing, R. A. & Bridle, A. H. 2002b, MNRAS, 336, 1161Google Scholar
Laing, R. A. & Bridle, A. H. 2013, MNRAS, 432, 1114Google Scholar
Laing, R. A. & Bridle, A. H. 2014, MNRAS, 437, 2405Google Scholar
Mack, K.-H., Klein, U., O'Dea, C. P., & Willis, A. G. 1997, A&AS, 123, 423Google Scholar
Mullin, L. M. & Hardcastle, M. J. 2009, MNRAS, 398, 1989Google Scholar
Perley, R. A., Bridle, A. H., & Willis, A. G. 1984, ApJS, 54, 291Google Scholar
Tavecchio, F., Maraschi, L., Sambruna, R. M., & Urry, C. M. 2000, ApJ, 544, L23Google Scholar
Waggett, P. C., Warner, P. J., & Baldwin, J. E. 1977, MNRAS, 181, 465Google Scholar
Wardle, J. F. C. & Aaron, S. E. 1997, MNRAS, 286, 425Google Scholar