Results 81 to 90 of about 183 (149)

Investigating the Emission Mechanism in the Spatially Resolved Jets of Two z ≈ 3 Radio-loud Quasars

The Astrophysical Journal
This study focuses on high-redshift, z > 3, quasars where resolved X-ray jets remain underexplored in comparison to nearby sources. Building upon previous work, we identify and confirm extended kiloparsec-scale jets emission in two quasars (J1405+0415, z
Jaya Maithil, Daniel A. Schwartz, Aneta Siemiginowska, Preeti Kharb, Diana M. Worrall, John F. C. Wardle, Giulia Migliori, Chi C. Cheung, Bradford Snios, Doug B. Gobeille, Herman L. Marshall, Mark Birkinshaw   +11 more
doaj   +1 more source

The Radio‐Loud Narrow‐Line Quasar SDSS J172206.03+565451.6

The Astrophysical Journal, 2006
We report identification of the radio loud narrow-line quasar SDSS J172206.03+565451.6 which we found in the course of a search for radio loud narrow-line Active Galactic Nuclei (AGN). SDSSJ172206.03+565451.6 is only the ~4th securely identified radio loud narrow-line quasar and the second-most radio loudest with a radio index R_1.4 ~ 100-700.
Komossa, S., Voges, W., Adorf, H., Xu, D., Mathur, S., Anderson, S.   +5 more
openaire   +3 more sources

First Measurements of Black Hole Accretion and Radio-jet Timescales in a Young Quasar at the Edge of Reionization

The Astrophysical Journal
We present the first study dedicated to measuring the timescales for black hole accretion and jet launching in a quasar at the edge of reionization, PSO J352.4034–15.3373 at z = 5.832 ± 0.001.
Sofía Rojas-Ruiz, Emmanuel Momjian, Frederick B. Davies, Eduardo Bañados, Anna-Christina Eilers, Sarah B. Bosman, Bhargav Vaidya, Chris Carilli, Chiara Mazzucchelli, Thomas Connor, Yana Khusanova   +10 more
doaj   +1 more source

High-Redshift Quasars at z ≥ 3—III: Parsec-Scale Jet Properties from Very Long Baseline Interferometry Observations

Universe
High-redshift active galactic nuclei (AGN) provide key insights into early supermassive black hole growth and cosmic evolution. This study investigates the parsec-scale properties of 86 radio-loud quasars at z ≥ 3 using very long baseline interferometry (
Shaoguang Guo, Tao An, Yuanqi Liu, Chuanzeng Liu, Zhijun Xu, Yulia Sotnikova, Timur Mufakharov, Ailing Wang   +7 more
doaj   +1 more source

Evidence for quasar fast outflows being accelerated at the scale of tens of parsecs. [PDF]

Sci Adv, 2022
He Z, Liu G, Wang T, Mou G, Green R, Bian W, Wang H, Ho LC, Sun M, Shen L, Arav N, Chen C, Wu Q, Guo H, Lin Z, Li J, Yi W.   +16 more
europepmc   +1 more source

Monster Radio Jet (>66 kpc) Observed in Quasar at z ∼​​​​​ 5

The Astrophysical Journal Letters
We present the discovery of a large extended radio jet associated with the extremely radio-loud quasar J1601+3102 at z  ∼​​​​​ 5 from subarcsecond resolution imaging at 144 MHz with the International LOFAR Telescope.
Anniek J. Gloudemans, Frits Sweijen, Leah K. Morabito, Emanuele Paolo Farina, Kenneth J. Duncan, Yuichi Harikane, Huub J. A. Röttgering, Aayush Saxena, Jan-Torge Schindler   +8 more
doaj   +1 more source

Soft gamma rays from low accreting supermassive black holes and connection to energetic neutrinos. [PDF]

Nat Commun, 2021
Kimura SS, Murase K, Mészáros P.
europepmc   +1 more source

High-Redshift, Radio-Loud Quasars

, 2000
I discuss two programs to study radio-loud quasars at high (z>4) redshift. Quasars are the most luminous, non-transient objects known and are observed to the earliest cosmic epochs. At lower redshifts, radio-loud quasars are associated with host galaxies having deVaucoleurs profiles. By association, identifying and studying a sample of high-redshift,
openaire   +2 more sources

Do All the Quasars and High-excitation Radio Galaxies (HERGs) in the 3CRR Catalog Contain a Magnetically Arrested Disk (MAD)?

The Astrophysical Journal
Based on the magnetization, an accretion disk with a large-scale magnetic field can be separated into either standard and normal evolution or magnetically arrested disk (MAD), which are difficult to identify from observations. It is still unclear whether
Shuang-Liang Li, Wenwen Zuo, Xinwu Cao
doaj   +1 more source

Broad Absorption Line Quasars and the Radio‐Loud/Radio‐Quiet Dichotomy [PDF]

Publications of the Astronomical Society of the Pacific, 1999
The observation that the extremely broad, blueshifted absorption troughs which characterize broad absorption line quasars (BALQs) occur exclusively in radio-quiet quasars (RQQs) suggests that this class of active galactic nuclei (AGN) may offer important clues to the radio-loud/radio-quiet (RL/RQ) dichotomy in quasars.
openaire   +2 more sources