Fanaroff-Riley classification

From Wikipedia, the free encyclopedia
Jump to: navigation, search

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-darkened. 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[edit]

References[edit]

  1. ^ 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: 31P–36P. Bibcode:1974MNRAS.167P..31F. 
  2. ^ Tsinganos, Kanaris C.; T. Thomas P., Ray; Stute, Martin (2009). Protostellar Jets in Context. Astrophysics and Space Science Proceedings. Springer. p. 276. ISBN 9783642005763. Retrieved 2013-01-11. 
  3. ^ "Fanaroff-Riley Classification". NASA/IPAC Extragalactic Database (NED). Caltech. Retrieved 11 January 2013.