Astronomy:Fanaroff-Riley classification
The Fanaroff-Riley classification is a scheme created by B.L. Fanaroff and J.M. Riley in 1974,[1] which is used to distinguish radio galaxies with active nuclei based on their radio luminosity or brightness of their radio emissions in relation to their hosting environment. Class I (abbreviated FR-I) are sources whose luminosity decreases as the distance from the central galaxy or quasar host increase, while Class II (FR-II) sources exhibit increasing luminosity in the lobes. These sources are called also edge-brightened. This distinction is important because it presents a direct link between the galaxy's luminosity and the way in which energy is transported from the central region and converted to radio emission in the outer parts.[2][3]
See also
References
- ā Fanaroff, Bernard L., Riley Julia M.; Riley (May 1974). "The morphology of extragalactic radio sources of high and low luminosity". Monthly Notices of the Royal Astronomical Society 167: 31Pā36P. doi:10.1093/mnras/167.1.31p. Bibcode: 1974MNRAS.167P..31F.
- ā Tsinganos, Kanaris C.; T. Thomas P., Ray; Stute, Martin (2009). Protostellar Jets in Context. Astrophysics and Space Science Proceedings. Springer. p. 276. ISBN 9783642005763. https://books.google.com/books?id=OvInhhp88HMC. Retrieved 2013-01-11.
- ā "Fanaroff-Riley Classification". NASA/IPAC Extragalactic Database (NED). Caltech. http://ned.ipac.caltech.edu/level5/Glossary/Essay_fanaroff.html. Retrieved 11 January 2013.
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