Results 11 to 20 of about 18,849 (212)
The diversity of quasars unified by accretion and orientation
Nature, 2014 Quasars are rapidly accreting supermassive black holes at the center of massive galaxies. They display a broad range of properties across all wavelengths, reflecting the diversity in the physical conditions of the regions close to the central engine ...
Ho, Luis C., Shen, Yue
core +3 more sources
Spectroscopic follow-up of double quasar candidates [PDF]
Monthly Notices of the Royal Astronomical Society, 2018 8 pages, 7 figures, 5 tables (full tables 1 and 3-5 are available online in a machine-readable ASCII format at https://grupos.unican.es/glendama/LQLM_results.htm). Accepted for publication in MNRAS (uncorrected version)
Shalyapin, V. N. +3 more
openaire +2 more sources
The Astrophysical Journal, 2023 Dual quasars at small physical separations are an important precursor phase of galaxy mergers, ultimately leading to the coalescence of the two supermassive black holes.
Arran C. Gross +10 more
doaj +1 more source
The Astrophysical Journal, 2023 Dual and off-nucleus active supermassive black holes are expected to be common in the hierarchical structure formation paradigm, but their identification at parsec scales remains a challenge due to strict angular resolution requirements.
Yu-Ching Chen +7 more
doaj +1 more source
Pictor A: A new double-peaked emission-line quasar [PDF]
The Astrophysical Journal, 1995 uu-encoded compressed tar of postscript files.
Sulentic, J. W. +3 more
openaire +2 more sources
Blueshifted Fe ii and Balmer Broad Emission lines in a Reddened Quasar
The Astrophysical Journal, 2023 We present detailed analysis of the optical and near-infrared spectrum of the reddened radio-loud quasar F2M J154043.74+492323.9 with strong optical Fe ii emission of ${R}_{4570}\equiv \tfrac{\mathrm{Fe}\,{\rm\small{II}}\lambda \lambda \,4434,4684}{{\rm ...
Yipeng Zhou +3 more
doaj +1 more source
The Pan-STARRS1 z > 5.6 Quasar Survey. III. The z ≈ 6 Quasar Luminosity Function
The Astrophysical Journal, 2023 We present the z ≈ 6 type-1 quasar luminosity function (QLF), based on the Pan-STARRS1 (PS1) quasar survey. The PS1 sample includes 125 quasars at z ≈ 5.7–6.2, with −28 ≲ M _1450 ≲ −25.
Jan-Torge Schindler +11 more
doaj +1 more source
Modelling the Gravitational Lens of the Double Quasar [PDF]
Symposium - International Astronomical Union, 1982 The discovery of the double quasar (Walsh ET AL. 1979) provides an opportunity to study the mass distribution of elliptical galaxies and clusters of galaxies. This has been done initially by Young ET AL. (1981) who produced a model to account for the image positions and intensities. Since then VLBI observations have been made of 0957+561A and B (Porcas
P. K. Moore, S. M. Harding
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Direct evidence of the receding `torus' around central nuclei of powerful radio sources [PDF]
, 2004 The presence of obscuring material (or a dusty `torus') in active galactic nuclei (AGN) is central to the unification model for AGN. Two models, the multi-population model for radio sources and the receding torus model, are capable of describing ...
Allen +38 more
core +1 more source
Unusual double-peaked emission in the SDSS quasar J093201.60+031858.7 [PDF]
New Astronomy, 2011 Author list updated in version 2; 17 pages; 3 figures; accepted for publication in New ...
Barrows, R. Scott +4 more
openaire +2 more sources