Results 101 to 110 of about 18,958 (240)
On probing the properties of QSOs through their proximity effects on the intergalactic medium
, 2011 The proximity effect (PE) of QSOs is believed to be useful in constraining the QSO lifetime. Observations on the PE so far, however, give apparently contradictory results -- some are consistent with a long QSO lifetime (>~ a few 10^7 yr), but others ...
Adelberger +31 more
core +1 more source
Companions of Qsos at Redshift 1.1 [PDF]
, 1994 We discuss broad- and narrow-band imaging of 7 arcmin fields of 14 QSOs with redshift ~1.1. The narrow-band filters were chosen to detect redshifted [O II] 3727A, and the broad bands are R and I, which correspond to rest wavelengths {}~3300A and ~3800A ...
Crampton, D. +2 more
core +2 more sources
The Astrophysical Journal Supplement Series, 2023 We search for quasi-stellar objects (QSOs) in a wide area of the south ecliptic pole (SEP) field, which has been and will continue to be intensively explored through various space missions. For this purpose, we obtain deep broadband optical images of the
Woowon Byun +20 more
doaj +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
QSO Environments at Intermediate Redshifts [PDF]
, 2001 We have made a survey of quasar environments at 0.5 < z < 0.8, using a sample of both radio-loud and radio-quiet quasars matched in B-band luminosity. Our observations include images of background control fields to provide a good determination of the field galaxy counts.
Margrethe Wold +4 more
openaire +3 more sources
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
A Candidate Dual QSO at Cosmic Noon
The Astrophysical Journal Letters, 2023 We report the discovery of a candidate dual QSO at z = 1.889, a redshift that is in the era known as “cosmic noon” where most of the universe’s black hole and stellar mass growth occurred.
Eilat Glikman +8 more
doaj +1 more source
FeII/MgII Emission Line Ratios of QSOs. II. z>6 Objects
, 2004 Near-infrared spectra of four QSOs located at $z>6$ are obtained with the OH-airglow suppressor mounted on the Subaru telescope. The FeII/MgII emission-line ratios of these QSOs are examined by the same fitting algorithm as in our previous study of $z6 ...
Fumihide Iwamuro +8 more
core +1 more source
The Continuum Slopes of Optically Selected QSOs [PDF]
, 1996 Quasi-simultaneous optical/near-IR photometry is presented for a sample of 37 luminous optically selected QSOs drawn from the Large Bright QSO Survey. Most of the QSOs have decreased in brightness since discovery; this is expected in flux-limited samples.
Cristiani +2 more
core +3 more sources
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