Results 71 to 80 of about 94,086 (264)
Astronomische Nachrichten, EarlyView.ABSTRACT The goal of this study is to confirm the feasibility of the use of digitized low dispersive MtWilson Michigan Southern Sky Hα$$ \alpha $$ survey astronomical photographic plates for modern astrophysical research. The detection of highly redshifted objects, such as early galaxies and quasars, is fundamental to understanding the universe's ...
Tauseef Ahmad Zafar +3 more
wiley +1 more source
Understanding extreme quasar optical variability with CRTS – II. Changing-state quasars [PDF]
Monthly notices of the Royal Astronomical Society, 2019 We present the results of a systematic search for quasars in the Catalina Real-time Transient Survey exhibiting both strong photometric variability and spectroscopic variability over a decadal baseline. We identify 111 sources with specific patterns of
M. Graham +10 more
semanticscholar +1 more source
Optical and radio properties of giant radio quasars: Central black hole characteristics
, 2012 We analysed the optical and radio properties of lobe-dominated giant-sized (> 0.72 Mpc) radio quasars and compared the results with those derived for a sample of smaller radio sources to determine whether the large size of some extragalactic radio ...
Jamrozy, M., Kuźmicz, A.
core +1 more source
Quasar-galaxy associations [PDF]
Monthly Notices of the Royal Astronomical Society, 1995 uuencoded Postscript file (including figures and tables), SUSSEX-AST 94/8 ...
Thomas, P. A. +2 more
openaire +4 more sources
Hidden No More: Spotlight on Tidal Disruption Events in Active Galactic Nuclei
Astronomische Nachrichten, EarlyView.ABSTRACT Tidal disruption events (TDEs) are typically discovered in previously quiescent galaxies. However, earlier studies have revealed a handful of TDEs occurring in pre‐existing active galactic nuclei (AGN). We discuss AT2019aalc, a promising TDE candidate in an AGN, and compare it to similar sources.
Patrik Milán Veres
wiley +1 more source
Impact of Radio-mode Feedback on the Covering Fraction of the Circumgalactic Medium of Quasars
The Astrophysical JournalUtilizing data from the Low-Frequency Array Two-meter Sky Survey and the Sloan Digital Sky Survey, we assemble a sample of 1469 projected quasar pairs with detected radio emissions from foreground quasars, as well as a control sample of 5846 pairs ...
Wen-Qiang Liang +4 more
doaj +1 more source
Gemini GNIRS Near-infrared Spectroscopy of 50 Quasars at z ≳ 5.7 [PDF]
Astrophysical Journal, 2018 We report initial results from a large Gemini program to observe z ≳ 5.7 quasars with GNIRS near-IR spectroscopy. Our sample includes 50 quasars with simultaneous ∼0.85–2.5 μm spectra covering the rest-frame ultraviolet and major broad emission lines ...
Yue Shen +14 more
semanticscholar +1 more source
Gaussian Processes for Predictive QSAR Modeling of Chromatographic Processes
Biotechnology and Bioengineering, EarlyView.ABSTRACT Chromatography is a key unit operation in the biopharmaceutical manufacturing process used for protein purification and polishing. Design and optimization of these processes are resource‐intensive resulting from the complex combinatorial design space.
Harini Narayanan +7 more
wiley +1 more source
The Astrophysical Journal Supplement SeriesWe present the quasar catalog from Data Releases 10 to 12 of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) Quasar Survey, comprising quasars observed between 2021 September and 2024 June. We robustly identified 11,346 quasars, of
Bing Lyu +11 more
doaj +1 more source
Circum-Galactic Medium in the Halo of Quasars
Frontiers in Astronomy and Space Sciences, 2017 The properties of circum-galactic gas in the halo of quasar host galaxies are investigated analyzing Mg II 2800 and C IV 1540 absorption-line systems along the line of sight close to quasars.
Riccardo Ottolina +6 more
doaj +1 more source