Results 81 to 90 of about 282 (177)

A Dichotomy in the 1–24 GHz Parsec-scale Radio Spectra of Radio-quiet Quasars

The Astrophysical Journal
We present the parsec-scale radio spectra of a representative sample of 13 Palomar–Green radio-quiet quasars, based on our new Very Long Baseline Array (VLBA) observations at 8.4 and 23.6 GHz and our earlier VLBA studies at 1.5 and 5.0 GHz.
Sina Chen, Ari Laor, Ehud Behar, Ranieri D. Baldi, Joseph D. Gelfand, Amy E. Kimball   +5 more
doaj   +1 more source

Jet Power and Electron Cooling in Fermi Blazars: Constraints from One-zone Leptonic Spectral Energy Distribution Modeling

The Astrophysical Journal
Blazars, with relativistic jets aligned to our line of sight, provide key laboratories for studying jet physics and accretion. We model the spectral energy distributions of 556 Fermi-detected blazars using JetSet to characterize external photon fields ...
X. Z. Zhao, Y. M. Pu, Y. G. Zheng, S. J. Kang   +3 more
doaj   +1 more source

Multi-messenger emission characteristics of blazars

Frontiers in Astronomy and Space Sciences
Multi-messenger observations and theories of astrophysical objects are rapidly becoming a critical research area in the astrophysics scientific community. In particular, point-like objects such as BL Lacertae (BL Lac) objects, flat-spectrum radio quasars
Ronald Gamble, Ronald Gamble, Ronald Gamble, Jordan Forman, Amethyst Barnes, Gokul Srinivasaragavan, Gokul Srinivasaragavan, Isiah Holt, Isiah Holt, Marvin Jones, Marvin Jones   +10 more
doaj   +1 more source

High energy properties of the flat spectrum radio quasar 4C 50.11

, 2016
12 pages, 7 figures, RAA ...
Zhou, Jianeng, Jithesh, V., Liang, Chen, Wang, Zhongxiang   +3 more
openaire   +2 more sources

UEG Week 2025 Oral Presentations

United European Gastroenterology Journal, Volume 13, Issue S8, Page S7-S188, October 2025.
wiley   +1 more source

The Study of Jet Formation Mechanism in Fermi Blazars

The Astrophysical Journal
The origin of jet launching mainly comes from two mechanisms: the Blandford–Znajek (BZ) mechanism and the Blandford–Payne (BP) mechanism. However, it is in debate which one is dominating in blazars.
Shangchun Xie, Zhihao Ouyang, Jingyu Wu, Hubing Xiao, Shaohua Zhang, Yongyun Chen, Zhijian Luo, Junhui Fan   +7 more
doaj   +1 more source

A one-parameter two-zone leptonic model for the blazar sequence

Astronomy & Astrophysics
Blazars, a subclass of radio-loud active galactic nuclei with relativistic jets aligned close to our line of sight, emit highly variable nonthermal radiation across the electromagnetic spectrum.
Boula S., Mastichiadis A., Kazanas D.
doaj   +1 more source

UEG Week 2025 Moderated Posters

United European Gastroenterology Journal, Volume 13, Issue S8, Page S189-S802, October 2025.
wiley   +1 more source

The Statistical Analysis of GeV Spectral Breaks in Bright Gamma-Ray Flat-spectrum Radio Quasars

The Astrophysical Journal Supplement Series
We present the statistical results of GeV spectral breaks of bright gamma-ray flat-spectrum radio quasars (FSRQs) in the energy range of 0.1–10 GeV based on New Pass 8 data of the Large Area Telescope on board Fermi Gamma-Ray Space Telescope.
K. R. Zhu, J. M. Chen, L. Zhang
doaj   +1 more source

UEG Week 2025 Poster Presentations

United European Gastroenterology Journal, Volume 13, Issue S8, Page S803-S1476, October 2025.
wiley   +1 more source