Results 31 to 40 of about 111,241 (293)
REVERBERATION RESPONSES IN LIGHT CURVES OF THE Q2237+0305 QUASAR [PDF]
Radio Physics and Radio Astronomy, 2018 Purpose: Studying the spatial structure of the quasar in the Q2237+0305 gravitational lens system in optical spectral range; estimating the central black hole mass.
L. A. Berdina +2 more
doaj +1 more source
A Significantly Neutral Intergalactic Medium Around the Luminous z = 7 Quasar J0252–0503 [PDF]
Astrophysical Journal, 2020 Luminous z ≥ 7 quasars provide direct probes of the evolution of supermassive black holes (SMBHs) and the intergalactic medium (IGM) during the epoch of reionization (EoR).
Feige Wang +16 more
semanticscholar +1 more source
Composite Quasar Spectra from the Sloan Digital Sky Survey [PDF]
, 2001 We have created a variety of composite quasar spectra using a homogeneous data set of over 2200 spectra from the Sloan Digital Sky Survey (SDSS). The quasar sample spans a redshift range of 0.044 ≤ z ≤ 4.789 and an absolute r' magnitude range of -18.0 to
S. C. D. E. V. Berk, E. al.
semanticscholar +1 more source
THE PROPERTIES OF QUASAR HOSTS AT THE PEAK OF THE QUASAR ACTIVITY [PDF]
The Astrophysical Journal, 2009 We present near-infrared imaging obtained with ESO VLT/ISAAC of a sample of 16 low luminosity radio-quiet quasars at the epoch around the peak of the quasar activity (2 < z < 3), aimed at investigating their host galaxies. For 11 quasars, we are able to detect the host galaxies and derive their properties, while for the other five quasars, upper ...
Kotilainen J. K. +5 more
openaire +5 more sources
H0LiCOW – IX. Cosmographic analysis of the doubly imaged quasar SDSS 1206+4332 and a new measurement of the Hubble constant [PDF]
Monthly notices of the Royal Astronomical Society, 2018 We present a blind time-delay strong lensing (TDSL) cosmographic analysis of the doubly imaged quasar SDSS 1206+4332 . We combine the relative time delay between the quasar images, Hubble Space Telescope imaging, the Keck stellar velocity dispersion of ...
S. Birrer +18 more
semanticscholar +1 more source
The Astrophysical Journal, 2002 In a survey of quasar candidates selected by matching the FIRST and 2MASS catalogs, we have found two extraordinarily red quasars. FIRST J013435.7-093102 is a 1 Jy source at z=2.216 and has B-K > 10, while FIRST J073820.1+275045 is a 2.5 mJy source at z=1.985 with B-K = 8.4.
Mark Lacy +9 more
openaire +3 more sources
The Astrophysical Journal Letters, 2022 We report the discovery of giant (50−100 kpc) [O ii ] emitting nebulae with MUSE in the field of TXS 0206−048, a luminous quasar at z = 1.13. “Down-the-barrel” UV spectra of the quasar show absorption at velocities coincident with those of the extended ...
Sean D. Johnson +12 more
doaj +1 more source
The Astrophysical Journal Supplement Series, 2023 Since their first discovery, quasars have been essential probes of the distant Universe. However, due to our limited knowledge of its nature, predicting the intrinsic quasar continua has bottlenecked their usage.
Zechang Sun, Yuan-Sen Ting, Zheng Cai
doaj +1 more source
Kiloparsec-scale ALMA Imaging of [C ii] and Dust Continuum Emission of 27 Quasar Host Galaxies at z ∼ 6 [PDF]
Astrophysical Journal, 2020 We present a study of the [C ii] 158 μm line and underlying far-infrared (FIR) continuum emission of 27 quasar host galaxies at z ∼ 6, traced by the Atacama Large Millimeter/submillimeter Array at a spatial resolution of ∼1 physical kpc.
B. Venemans +14 more
semanticscholar +1 more source
A Hubble Diagram for Quasars [PDF]
Frontiers in Astronomy and Space Sciences, 2015 The cosmological model is at present not tested between the redshift of the farthest observed supernovae (z ~ 1.4) and that of the Cosmic Microwave Background (z ~ 1,100). Here we introduce a new method to measure the cosmological parameters: we show that quasars can be used as "standard candles" by employing the non-linear relation between their ...
Guido Risaliti +4 more
openaire +10 more sources