In reply to parejkoj,
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Actually, that's exactly the same paper as the one you cited above.
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Sorry parejkoj, the link I provided above was to Leighly’s second paper. This is a link to her first paper.
I agree to no longer mention "B" in this thread.
Quasar Clustering
The paper I linked to stated that there were 4 times more than random clustering of quasars. How many merges were you thinking of? I remember people arguing, four or five years ago, that there was no clustering of quasars (i.e. quasars were randomly distributed), that any quasars observed in close proximity were due to gravitational lensing. I thought the finding of quasar binaries to be interesting, from the standpoint of close proximity of the quasars in question and how the quasars must be fed. Also I thought that typically during a merger one of the BH was ejected.
BH Intrinsic Magnetic Field
The MECO associated observations which are based on 25 years of quasar observations are interesting as the observed quasar structures require an intrinsic black hole magnetic field as the structures have been observationally located between the disc and BH. An accretion disc generated magnetic field cannot create a structure in that location. A BH generated magnetic field is required. Also interesting is the comment in the paper that very strong magnetic fields create electron positron pairs in the vacuum. I will provide a link to the MECO, paper. It is necessary for you read to read the MECO paper before you comment.
High Redshift Dusty Quasars
I will provide a link to a paper that explains the theoretical problems which makes it difficult for "dust" to form, in general.
Lack of Quasar Time Dilation with Redshift/Lack of Quasar Metallicity Evolution with Redshift
I will provide a link to Hawkins paper that notes a lack of time dilation for quasars. There is as others have noted observed time dilation for super nova. The lack of quasar time dilation and the lack quasar evolution of metallicity could be viewed as a paradox.
Lineless QSO/Naked QSO
PHL 1811: The Local Prototype of the Lineless High-z SDSS QSOs, by Karen Leighly et al.
http://arxiv.org/abs/astro-ph/0402535
This is a link to Hawkins’ paper on naked AGN. PHL 1811 seems to be similar to the Naked AGN, in that it has an anomalous lack of emission lines (i.e. It is lineless.) PHL 1811 in addition to being lineless is anomalous as it “ is between 13 and 450 times fainter in X-rays than other quasars with the same UV luminosity.”
“Naked active galactic nuclei”, by M. Hawkins
http://arxiv.org/abs/astro-ph/0406163v1
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In this paper we report the discovery of a new class of active galactic nucleus in which although the nucleus is viewed directly, no broad emission lines are present. The results are based on a survey for AGN in which a sample of about 800 quasars and emission line galaxies were monitored yearly for 25 years. Among the emission line galaxies was the expected population of Seyfert 2 galaxies with only narrow forbidden lines in emission, and no broad lines. … …It is argued that these objects can only be Seyfert 1 galaxies in which the nucleus is viewed directly, but in which broad emission lines are completely absent.
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Such ‘naked’ AGN appear to be quite common, comprising roughly 10% of the sample of the emission line galaxies observed… …An interesting question which arises concerns the possibility that naked nuclei may be found among more luminous AGN in the quasar regime. This almost inevitably means that candidate objects will be at higher redshift, and much more difficult to identify without the help of a system of strong narrow forbidden lines. There is much anecdotal evidence from surveys based on UVX selection for objects with featureless spectra for which there is no plausible classification. Such objects are typically ignored for lack of observational evidence as to their nature. With information on variability, one can say a lot more.
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This is paper is interesting and seems to be some how related to Leighly and Hawkins’ observations.
“Discovery of a bright quasar without a massive host galaxy”, by Pierre Magain et al.
http://arxiv.org/abs/astro-ph/0509433
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Quasars are thought to be powered by the infall of matter onto a supermassive black hole at the centre of massive galaxies. As the optical luminosity of quasars exceeds that of their host galaxy, disentangling the two components can be difficult. This led in the 1990's to the controversial claim of the discovery of 'naked' quasars. Since then, the connection between quasars and galaxies has been well established. Here we report on the observation of a quasar lying at the edge of a gas cloud, whose size is comparable to that of a small galaxy, but whose spectrum shows no evidence for stars. The gas cloud is excited by the quasar itself. If a host galaxy is present, it is at least six times fainter than would normally be expected for such a bright quasar.
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