An evolutionary scheme for active-nucleus objects

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

5

Galactic Evolution, Galactic Nuclei, Quasars, Radio Sources (Astronomy), Seyfert Galaxies, Bl Lacertae Objects, Galactic Clusters, Luminosity, Stellar Evolution

Scientific paper

The features typical of active nuclei in galaxies and the conditions necessary for activity are discussed. QSO's may represent nuclei of luminous galaxies in an early, particularly violent evolutionary phase. The spectroscopic properties of the various species of quasar-like objects suggest a possible evolutionary sequence from those with Sy 0, I (Seyfert 1) spectra to Sy II, III spectra. An evolutionary scheme is outlined whereby the active nuclei in various types of galaxies would correspond to well-evolved QSO's belonging to either spheroidal /QSO(E)/ or flat /QSO(S)/ systems. These two kinds of QSO's may be either strong radio emitters /QSS(E)/ or weak radio emitters /QSG(E)/, QSG(S)/, a distinction which would manifest itself, in evolutionary terms, as the difference observed between the radio properties of radio galaxies and Seyferts, on the one hand, and normal E, S galaxies with low-activity nuclei, on the other. QSO(S)'s should be scores of times as common in the universe as QSO(E)'s; there may be as many as 10 to the -6th QSG(S)'s per cu Mpc. Such objects should contribute significantly to counts of blue 21-23 m starlike images.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

An evolutionary scheme for active-nucleus objects 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 An evolutionary scheme for active-nucleus objects, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and An evolutionary scheme for active-nucleus objects will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-928745

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.