Results 101 to 110 of about 10,418 (177)

Unveiling New Giant Radio Quasars from the TGSS Sky and Their Large-scale Environment

The Astrophysical Journal Supplement Series
Giant radio quasars (GRQs) are radiatively efficient radio-loud active galactic nuclei that propel large-scale radio jets with projected lengths of more than 0.7 Mpc. We report the discovery of 53 new GRQs within a redshift range of 0.14–2.38, as well as
Souvik Manik, Netai Bhukta, Sabyasachi Pal, Sushanta K. Mondal   +3 more
doaj   +1 more source

The transition from quasar radio-loud to radio-quiet state in the framework of the black hole scalability hypothesis

, 2010
There are several lines of evidence that active galactic nuclei (AGN) can be regarded as scaled-up X-ray binaries (XRB). The timescales of the evolutionary phenomena in these two classes are proportional to the black hole (BH) masses.
A. Marecki, Abazajian, Alexander, Antonucci, B. Swoboda, Barthel, Barvainis, Blundell, Blundell, Blundell, Blundell, Castro-Tirado, Chatterjee, Condon, Czerny, Elvis, Eracleous, Esin, Falcke, Fanaroff, Fender, Fender, Fender, Flesch, Ghisellini, Hough, Kaiser, Komissarov, Körding, Laor, Liu, Maccarone, Machalski, Marchesini, Marecki, Markert, Marscher, McHardy, Meier, Miller, Mirabel, Mirabel, Mirabel, Miyamoto, Méndez, Nipoti, Schneider, Shakura, Sikora, Sopp, Taylor, Türler, Ulvestad, Urry, Wang, White, Wu   +56 more
core   +1 more source

Discovery of a Radio-loud/Radio-quiet Binary Quasar

The Astrophysical Journal, 1999
8 pages, 3 figures, to appear in Astrophysical Journal ...
Brotherton, M. S., Gregg, Michael D., Becker, R. H., Laurent-Muehleisen, S. A., White, R. L., Stanford, S. A.   +5 more
openaire   +2 more sources

Optically Selected BL Lacertae Candidates from the Sloan Digital Sky Survey Data Release Seven

, 2009
We present a sample of 723 optically selected BL Lac candidates from the SDSS DR7 spectroscopic database encompassing 8250 deg^2 of sky; our sample constitutes one of the largest uniform BL Lac samples yet derived.
Anderson, S. F., Bahcall, N. A., Bizyaev, D., Brandt, W. N., Brewington, H., Diamond-Stanic, A. M., Fan, X., Hall, P. B., Kimball, A. E., Malanushenko, E., Malanushenko, V., Oravetz, D., Pan, K., Plotkin, Richard M., Richmond, M. W., Schneider, D. P., Shemmer, O., Simmonds, A., Snedden, S., Voges, W., York, D. G.   +20 more
core   +2 more sources

Broad Absorption Line Quasars and the Radio‐Loud/Radio‐Quiet Dichotomy [PDF]

Publications of the Astronomical Society of the Pacific, 1999
The observation that the extremely broad, blueshifted absorption troughs which characterize broad absorption line quasars (BALQs) occur exclusively in radio-quiet quasars (RQQs) suggests that this class of active galactic nuclei (AGN) may offer important clues to the radio-loud/radio-quiet (RL/RQ) dichotomy in quasars.
openaire   +2 more sources

First Measurements of Black Hole Accretion and Radio-jet Timescales in a Young Quasar at the Edge of Reionization

The Astrophysical Journal
We present the first study dedicated to measuring the timescales for black hole accretion and jet launching in a quasar at the edge of reionization, PSO J352.4034–15.3373 at z = 5.832 ± 0.001.
Sofía Rojas-Ruiz, Emmanuel Momjian, Frederick B. Davies, Eduardo Bañados, Anna-Christina Eilers, Sarah B. Bosman, Bhargav Vaidya, Chris Carilli, Chiara Mazzucchelli, Thomas Connor, Yana Khusanova   +10 more
doaj   +1 more source

Discovery of spectacular quasar-driven superbubbles in red quasars. [PDF]

Sci Adv, 2023
Shen L, Liu G, He Z, Zakamska NL, Glikman E, Greene JE, Hu W, Mou G, Wylezalek D, Rupke DSN.   +9 more
europepmc   +1 more source

Quasar x-ray spectra revisited [PDF]

A sample of 45 quasars observed by the Imaging Proportional Counter (IPC) on the Einstein satellite is used to re-examine the relationship between the soft (0.2-3.5 keV) X-ray energy index and radio-loudness.
Elvis, M., Mcdowell, J., Shastri, P., Wilkes, B. J.   +3 more
core   +1 more source

Investigating the Emission Mechanism in the Spatially Resolved Jets of Two z ≈ 3 Radio-loud Quasars

The Astrophysical Journal
This study focuses on high-redshift, z > 3, quasars where resolved X-ray jets remain underexplored in comparison to nearby sources. Building upon previous work, we identify and confirm extended kiloparsec-scale jets emission in two quasars (J1405+0415, z
Jaya Maithil, Daniel A. Schwartz, Aneta Siemiginowska, Preeti Kharb, Diana M. Worrall, John F. C. Wardle, Giulia Migliori, Chi C. Cheung, Bradford Snios, Doug B. Gobeille, Herman L. Marshall, Mark Birkinshaw   +11 more
doaj   +1 more source

The cluster environments of radio loud quasars

, 2001
5 pages, 3 figures, contribution to "Tracing Cosmic Evolution with Galaxy Clusters" (Sesto 2001), ASP Conference ...
Barr, J., Bremer, M., Baker, J., Lehnert, M.   +3 more
openaire   +3 more sources