Results 101 to 110 of about 20,094 (246)
Observational Constraints on Sunyaev–Zeldovich Effect Halos around High-z Quasars
The Astrophysical JournalWe present continuum observations from the Atacama Large Millimeter/submillimeter Array of 10 high-redshift (2.2 ≤ z ≤ 2.7) ultraluminous quasars (QSOs) and constrain the presence of hot, ionized, circumgalactic gas in a stacking analysis.
Kyle Massingill +6 more
doaj +1 more source
The Optical Polarization of Near-Infrared Selected QSOs
, 2001 Optical broad-band polarimetry is presented for near-infrared color-selected AGN classified QSOs based on their K-band luminosity. More than 10% of a sample of 70 QSOs discovered in the Two Micron All Sky Survey (2MASS) with J-K > 2 and M_K 3%), and ...
Cutri, R. M. +4 more
core +1 more source
The extended narrow-line region of two type-I quasi-stellar objects [PDF]
, 2013 We investigate the narrow-line region (NLR) of two radio-quiet QSOs, PG1012+008 and PG1307+085, using high signal-to-noise spatially resolved long-slit spectra obtained with FORS1 at the Very Large Telescope.
Albrecht, Marcus +6 more
core +3 more sources
, 2003 The QSO lifetime t_Q is one of the most fundamental quantities for understanding black hole and QSO evolution, yet it remains uncertain by several orders of magnitude. If t_Q is long, then only a small fraction of galaxies went through a luminous QSO phase. In contrast, a short lifetime would require most galaxies today to have undergone a QSO phase in
openaire +2 more sources
Photometric histories of QSOs - Two QSOs with large light amplitude
The Astrophysical Journal, 1975 PKS 1510--089, a QSO with a redshift z=0.361, has varied in B from 11.8 to 17.8 mag since 1899.6. At its brightest in 1948, PKS 1510--089 was optically one of the most luminous known objects in the universe if its redshift is cosmological. Its observed range in brightness, 5.4 mag, is larger than that known for any other QSO.
M. H. Liller, W. Liller
openaire +1 more source
The Plane Quasar Survey: First Data Release
The Astrophysical Journal Supplement SeriesWe present a sample of 305 QSO candidates having ∣ b ∣ < 30°, the majority with GALEX magnitudes near-UV < 18.75. To generate this sample, we apply UV–IR color selection criteria to photometric data from the Ultraviolet Galactic Plane Survey as part of ...
Jessica Werk +6 more
doaj +1 more source
, 2011 We present the results of infrared L-band (3-4 micron) slit spectroscopy of 30 PG QSOs at z < 0.17, the representative sample of local high-luminosity, optically selected AGNs. The 3.3 micron polycyclic aromatic hydrocarbon (PAH) emission feature is used
Ichikawa, Kohei +5 more
core +1 more source
Accretion-disk coronae in QSOs [PDF]
Publications of the Astronomical Society of the Pacific, 1991 Radiation pressure on gas in the hypothesized accretion disks of QSOs will result in a corona. Electrons of 340 kev, equivalent to Te∼3×108 K, may result in a significant. Compton optical depth for the implied mass loss rate. Comptonization of ultraviolet to 30 kev may result in contradiction to observations.
openaire +1 more source
A Diverse Population of z ∼ 2 ULIRGs Revealed by JWST Imaging
The Astrophysical Journal, 2023 Four ultraluminous infrared galaxies (ULIRGs) observed with JWST/NIRcam in the Cosmos Evolution Early Release Science program offer an unbiased preview of the z ∼ 2 ULIRG population.
J.-S. Huang +14 more
doaj +1 more source
, 2006 AIMS. To check whether the polar angle distribution of QSOs around nearby spiral galaxies is isotropic or not. METHODS. A statistical analysis of the polar angle distribution of large samples of QSOs from the SDSS survey and Monte Carlo simulations to ...
Abazajian +32 more
core +1 more source