Journal ArticleDOI
Unified models for active galactic nuclei and quasars
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TLDR
The straw person model (SPM) as mentioned in this paper has been proposed to explain the orientation effects of active galactic nuclei (AGN) and quasars in the line of sight (LOS) images.Abstract:
Because the critical central regions of Active Galactic Nuclei (AGN) and quasars are strongly nonspherical but spatially unresolved, orientation effects have been the source of much confusion. In fact, it now appears that much of the variety in AGN types is just the result of varying orientation relative to the line of sight. We can define an extreme hypothesis,, the straw person model (SPM), in which there are two basic types of AGN: the radio quiets and the radio louds. For each type there is a range in intrinsic luminosity, and the luminosity controls some properties such as the Fanaroff and Riley classes. However, at a given intrinsic luminosity, all other properties such as spectroscopic classification and VLBI component speeds are ascribed to orientation. This model is only a caricature of the unification idea, and is already ruled out on many grounds, but it will be useful for organizing the discussion. I’ll describe what I consider to be convincing evidence that orientation effects are important and widespread. The true situation may be in some sense half way between the SPM and the hypothesis that orientation doesn’t affect classification at aIl. To us optimists, the orienration cup is half full rather than half empty. Although it is too soon to say for sure, the hypothesis that most objects’ classifications would be different if seen from other directions is a tenable one today.read more
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Subaru Mid-Infrared Imaging of the Quadruple Lenses PG 1115+080 and B1422+231: Limits on Substructure Lensing*
TL;DR: In this paper, the anomalous optical and radio flux ratios of a quadruple lens system were obtained for mid-infrared imaging at 11.7 μm for the four-camera system PG 1115+080 and B1422+231.
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The properties of the extended warm ionised gas around low-redshift QSOs and the lack of extended high-velocity outflows
TL;DR: In this article, a detailed analysis of a large sample of 31 low-redshift, mostly radio-quiet type 1 quasi-stellar objects (QSOs) observed with integral field spectroscopy to study their extended emission-line regions (EELRs) was presented.
Journal ArticleDOI
XMM-Newton observations reveal AGN in apparently normal galaxies
Paola Severgnini,Alessandro Caccianiga,V. Braito,R. Della Ceca,Tommaso Maccacaro,Anna Wolter,Kazuhiro Sekiguchi,Toshiyuki Sasaki,Michitoshi Yoshida,Masayuki Akiyama,M. G. Watson,Xavier Barcons,Francisco J. Carrera,Wolfgang Pietsch,Natalie A. Webb +14 more
TL;DR: In this paper, a detailed analysis of 3 optically normal galaxies extracted from the XMM Bright Serendipitous Source Sample (BSS) was performed, which revealed the presence of an AGN in all of them.
Journal ArticleDOI
High-Velocity Bipolar Molecular Emission from an AGN Torus
Jack F. Gallimore,Moshe Elitzur,Moshe Elitzur,Roberto Maiolino,Alessandro Marconi,Alessandro Marconi,Christopher P. O'Dea,Dieter Lutz,Stefi A. Baum,Robert Nikutta,Caterina M. V. Impellizzeri,Richard Davies,Amy Kimball,Eleonora Sani +13 more
TL;DR: In this article, the authors detect CO emission from the nucleus of the Seyfert galaxy NGC 1068 and show that low-velocity (up to ±70 km s−1 relative to systemic) CO emission resolves into a 12 × 7 pc structure, roughly aligned with the nuclear radio source.
Journal ArticleDOI
Radio imaging of the Subaru/XMM–NewtonDeep Field– III. Evolution of the radio luminosity function beyond z= 1
Chris Simpson,Steve Rawlings,Rob Ivison,Rob Ivison,Masayuki Akiyama,Omar Almaini,E. J. Bradshaw,Scott Chapman,Robert Chuter,Scott M. Croom,James Dunlop,Sebastien Foucaud,Will G. Hartley +12 more
TL;DR: In this paper, the authors present spectroscopic and 11-band photometric redshifts for galaxies in the 100-μJy Subaru/XMM-NewtonDeep Field radio source sample.
References
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Phd by thesis
TL;DR: In this paper, a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) is presented.
Journal Article
Superluminal Radio Sources
J. A. Zensus,T. J. Pearson +1 more
TL;DR: There are now at least 23 radio sources in which apparent superluminal motion has been found as mentioned in this paper, and the effect is not limited to the classic examples like 3C 345, but is found in objects with a wide range of characteristic properties.