Results 71 to 80 of about 10,384 (186)

The rest-frame ultraviolet properties of radio-loud broad absorption line quasars

, 2012
We recently presented radio observations of a large sample of radio-loud broad absorption line (BAL) quasars from the SDSS and FIRST surveys, as well as a well matched sample of unabsorbed quasars, primarily to measure their radio spectral indices and ...
Allen, Antonucci, Becker, Becker, Becker, Boroson, Boroson, Brotherton, Brotherton, Bruni, Cano-Diaz, Condon, DiPompeo, DiPompeo, DiPompeo, DiPompeo, Elvis, Fanti, Fine, Gallagher, Ganguly, Ganguly, Ghosh, Gibson, Gregg, Gregg, Hall, Hewett, Hopkins, J. C. Runnoe, Jarvis, King, Knigge, Kriss, M. A. DiPompeo, M. S. Brotherton, Montenegro-Montes, Nemmen, O'Dea, Ogle, Peterson, Reichard, Richards, Richards, Runnoe, S. L. Cales, Schlegel, Shen, Silk, Spergel, Stocke, Vestergaard, Vestergaard, Weymann, Zhou   +54 more
core   +1 more source

[C ii] Properties and Far-infrared Variability of a z = 7 Blazar

The Astrophysical Journal Letters
We present millimeter observations of the host galaxy of the most distant blazar known, VLASS J041009.05−013919.88 (hereafter J0410–0139) at z = 7, using Atacama Large Millimeter/submillimeter Array (ALMA) and NOrthern Extended Millimeter Array (NOEMA ...
Eduardo Bañados, Yana Khusanova, Roberto Decarli, Emmanuel Momjian, Fabian Walter, Thomas Connor, Christopher L. Carilli, Chiara Mazzucchelli, Sofía Rojas-Ruiz, Bram P. Venemans   +9 more
doaj   +1 more source

The environment of active objects in the nearby universe

, 2002
We study the galaxy environment of active galaxies, radio-loud and radio-quiet quasars in the redshift range $0.1\leq z\leq0.25$. We use APM galaxies in order to explore the local galaxy overdensity and the $b_J-R$ colour distribution of neighbouring ...
Abell, Babul, Barrow, Baugh, Best, Diego G. Lambas, Dressler, Ebeling, Fisher, Georgina V. Coldwell, Héctor J. Martínez, Lilje, Martínez, McLure, Rees, Schechter, Silk, Smith, Toomre, Voit, Véron-Cetty, Wold, Wold, Yee, Yee   +24 more
core   +2 more sources

Disclosing the Radio Loudness Distribution Dichotomy in Quasars: An Unbiased Monte Carlo Approach Applied to the SDSS-FIRST Quasar Sample [PDF]

, 2012
We investigate the dichotomy in the radio loudness distribution of quasars by modelling their radio emission and various selection effects using a Monte Carlo approach. The existence of two physically distinct quasar populations, the radio-loud and radio-
B. C. Kelly, Blandford, E. Schinnerer, G. Zamorani, Garofalo, Hodge, Hughes, Ivezić, Ivezić, Ivezić, Jiang, Kimball, Kimball, Lacy, Laor, M. Baloković, Mahoney, Miller, Padovani, Peacock, Richards, Richards, Schinnerer, Schlegel, Schneider, Scoville, Sikora, Singal, Smolčić, Strittmatter, V. Smolčić, White, White, York, Ž. Ivezić   +34 more
core   +4 more sources

VLBA Observations ofz>4 Radio-loud Quasars

The Astronomical Journal, 2004
We present high resolution (< 20 mas) observations of the radio continuum emission at 1.4 GHz from three high-redshift quasars: J1053-0016 (z=4.29), 1235-0003 (z=4.69), and J0913+5919 (z=5.11), thereby doubling the number of z > 4 radio-loud quasars that have been imaged at mas resolution.
Momjian, Emmanuel, Petric, Andreea O., Carilli, Christopher L.   +2 more
openaire   +2 more sources

Impact of Radio-mode Feedback on the Covering Fraction of the Circumgalactic Medium of Quasars

The Astrophysical Journal
Utilizing data from the Low-Frequency Array Two-meter Sky Survey and the Sloan Digital Sky Survey, we assemble a sample of 1469 projected quasar pairs with detected radio emissions from foreground quasars, as well as a control sample of 5846 pairs ...
Wen-Qiang Liang, Zhi-fu Chen, Rui-Jing Lu, Jing Li, Zhe-Geng Chen   +4 more
doaj   +1 more source

Clear Evidence for Intranight Optical Variability in Radio-quiet Quasars [PDF]

, 2003
We present new clues to the problem of the radio loudness dichotomy arising from an extensive search for intranight optical variability in seven sets of optically luminous radio-quiet quasars and (radio-loud) BL Lacertae objects, which are matched in ...
Gopal-Krishna, Sagar, Ram, Stalin, C. S., Wiita, Paul J.   +3 more
core   +3 more sources

CONSTRAINING THE RADIO-LOUD FRACTION OF QUASARS ATz> 5.5 [PDF]

The Astrophysical Journal, 2015
Accepted for publication in ApJ. 3 Figures.
E. Bañados, B. P. Venemans, E. Morganson, J. Hodge, R. Decarli, F. Walter, D. Stern, E. Schlafly, E. P. Farina, J. Greiner, K. C. Chambers, X. Fan, H-W. Rix, W. S. Burgett, P. W. Draper, J. Flewelling, N. Kaiser, N. Metcalfe, J. S. Morgan, J. L. Tonry, R. J. Wainscoat   +20 more
openaire   +5 more sources

The Detection Rate of Associated Mg ii Absorption Lines in Quasars Depends on Their Radio Emission

The Astrophysical Journal
In active galactic nuclei, jet-driven feedback plays a significant role in influencing the properties of gas within their host galaxy and the circumgalactic medium.
Zhi-Fu Chen, Luis C. Ho
doaj   +1 more source

Near-infrared adaptive optics imaging of high redshift quasars [PDF]

, 2007
The properties of high redshift quasar host galaxies are studied, in order to investigate the connection between galaxy evolution, nuclear activity, and the formation of supermassive black holes.
Aldo Treves, Bower G. C., Bressan A., Hutchings J. B., Jari K. Kotilainen, Kotilainen J. K., Michela Uslenghi, Renato Falomo, Riccardo Scarpa   +8 more
core   +2 more sources