Results 101 to 110 of about 85,255 (272)

Quasar Clustering from SDSS DR5: Dependences on Physical Properties

, 2008
Using a homogenous sample of 38,208 quasars with a sky coverage of $4000 {\rm deg^2}$ drawn from the SDSS Data Release Five quasar catalog, we study the dependence of quasar clustering on luminosity, virial black hole mass, quasar color, and radio ...
Abazajian, Abazajian, Adelberger, Adelman-McCarthy, Andrew J. Connolly, Basilakos, Blanton, Coil, Cole, Constantin, Courteau, Croft, Croton, Daniel E. Vanden Berk, David H. Weinberg, Donald P. Schneider, Eisenstein, Fan, Ferrarese, Ferrarese, Francesco Shankar, Gao, Gebhardt, Gordon T. Richards, Gunn, Gunn, Haiman, Hennawi, Ho, Hogg, Hopkins, Hopkins, Hopkins, Hopkins, Jiang, Jing, Joseph F. Hennawi, King, Kollmeier, Kormendy, Lidz, Lupton, Magorrian, Martini, Michael A. Strauss, Mo, Myers, Myers, Myers, Myers, Neta A. Bahcall, Nicholas P. Ross, Padmanabhan, Padmanabhan, Patrick B. Hall, Pier, Reichard, Richards, Richards, Richards, Richstone, Robert J. Brunner, Ross, Schlegel, Schlegel, Schneider, Shankar, Shankar, Shen, Shen, Shen, Shen, Shen, Silk, Smith, Spergel, Stoughton, Tinker, Tremaine, Vestergaard, Wechsler, Wetzel, Wyithe, Wyithe, Wyithe, Xiaohui Fan, Yen-Ting Lin, York, Yue Shen, Zehavi, Zel'dovich   +90 more
core   +1 more source

The Jets in Micro-Quasars and Quasars: A Comparison [PDF]

Highlights of Astronomy, 2005
AbstractThe discovery of relativistic jets in radio emitting X-ray binaries in our own galaxy has led to the term ‘microquasar’ being coined for these objects. In this paper the properties of microquasars are compared with those of quasars and radio galaxies, with the aim of trying to see how the similarities and differences can inform us about the ...
openaire   +1 more source

Probing ~100 AU Intergalactic MgII Absorbing "Cloudlets" with Quasar Microlensing

, 2006
Intergalactic MgII absorbers are known to have structures down to scales ~ 10^{2.5} pc, and there are now indications that they may be fragmented on scales
Kayser R., Subo Dong
core   +3 more sources

Time Dilation and Quasar Variability

, 2001
The timescale of quasar variability is widely expected to show the effects of time dilation. In this paper we analyse the Fourier power spectra of a large sample of quasar light curves to look for such an effect.
Cristiani S., Hawkins M. R. S., Hook I. M., M. R. S. Hawkins, Pelt J.   +4 more
core   +2 more sources

Redshift Evolution of the X-Ray and Ultraviolet Luminosity Relation of Quasars: Calibrated Results from SNe Ia

The Astrophysical Journal
Quasars could serve as standard candles if the relation between their ultraviolet (UV) and X-ray luminosities can be accurately calibrated. Previously, we developed a model-independent method to calibrate quasar standard candles using the distance ...
Xiaolei Li, Ryan E. Keeley, Arman Shafieloo   +2 more
doaj   +1 more source

Modeling quasar variability through self-organizing map-based neural process [PDF]

Serbian Astronomical Journal
Conditional Neural Process (QNPy) has shown to be a good tool for modeling quasar light curves. However, given the complex nature of the source and hence the data represented by light curves, processing could be time-consuming.
Čvorović-Hajdinjak I.
doaj   +1 more source

The Relation Between Quasar and Merging Galaxy Luminosity Functions and the Merger-Induced Star Formation Rate of the Universe

, 2006
Using a model for self-regulated growth of black holes (BHs) in mergers involving gas-rich galaxies, we study the relationship between quasars and the population of merging galaxies and predict the merger-induced star formation rate density of the ...
Allen D. A., Bouchet P., Brant Robertson, Busha M. T., Jorgensen I., Joseph R. D., Kormendy J., Lars Hernquist, Magdziarz P., Melnick J., Oliva E., Philip F. Hopkins, Rachel S. Somerville, Richstone D., Small T. A., Soares D. S. L., Thomas J. Cox, Yuexing Li   +17 more
core   +1 more source

The properties of the quasars astrometric solution in Gaia DR2 [PDF]

, 2018
S. Liao, B. Bucciarelli, Zhaoxiang Qi, Sufen Guo, Zihuang Cao, Zhenghong Tang   +5 more
openalex   +1 more source

ISO Observations of Quasars and Quasar Hosts [PDF]

, 1997
The Infrared Space Observatory (ISO), launched in November 1995, allows us to measure the far-infrared (far-IR) emission of quasars in greater detail and over a wider energy range than previously possible. In this paper, preliminary results in a study of the 5--200 $μm$ continuum of quasars and active galaxies are presented.
openaire   +2 more sources

First Results from the JWST Early Release Science Program Q3D: Powerful Quasar-driven Galactic Scale Outflow at z = 3

The Astrophysical Journal
Quasar-driven galactic outflows are a major driver of the evolution of massive galaxies. We report observations of a powerful galactic-scale outflow in a z = 3 extremely red and intrinsically luminous ( L _bol ≃ 5 × 10 ^47 erg s ^−1 ) quasar SDSSJ1652 ...
Andrey Vayner, Nadia L. Zakamska, Yuzo Ishikawa, Swetha Sankar, Dominika Wylezalek, David S. N. Rupke, Sylvain Veilleux, Caroline Bertemes, Jorge K. Barrera-Ballesteros, Hsiao-Wen Chen, Nadiia Diachenko, Andy D. Goulding, Jenny E. Greene, Kevin N. Hainline, Fred Hamann, Timothy Heckman, Sean D. Johnson, Hui Xian Grace Lim, Weizhe Liu, Dieter Lutz, Nora Lützgendorf, Vincenzo Mainieri, Ryan McCrory, Grey Murphree, Nicole P. H. Nesvadba, Patrick Ogle, Eckhard Sturm, Lillian Whitesell   +27 more
doaj   +1 more source