Results 21 to 30 of about 38,287 (310)
Origin of Blazar Activity [PDF]
Symposium - International Astronomical Union, 1999 Models of Blazars based on the propagation of finite discontinuities or fronts in the Poynting flux jet from the innermost regions of an accretion disk around a black hole are discussed. Such fronts may be responsible for short time–scale (from less than hours to days) flares in different wavebands from high frequency radioband to TeV, with delay in ...
M. M. Romanova
openaire +4 more sources
The space density of z>4 blazars [PDF]
Monthly notices of the Royal Astronomical Society, 2019 High redshift blazars are an important class of Active Galactic Nuclei (AGN) that can provide an independent estimate of the supermassive black-hole mass function in high redshift radio-loud AGN without the bias due to absorption along the line-of-sight.
Antón, Sonia +11 more
core +4 more sources
Leptohadronic multi-messenger modeling of 324 gamma-ray blazars [PDF]
Astronomy & Astrophysics, 2023 The origin of the diffuse astrophysical neutrino flux observed by the IceCube experiment is still under debate. Multiple associations have been reported between high-energy neutrino events and individual blazars, such as the source TXS 0506+056, which ...
X. Rodrigues +5 more
semanticscholar +1 more source
Correlating High-energy IceCube Neutrinos with 5BZCAT Blazars and RFC Sources [PDF]
Astrophysical Journal Letters, 2023 We investigate the possibility that blazars in the Roma-BZCAT Multifrequency Catalogue of Blazars (5BZCAT) are sources of the high-energy astrophysical neutrinos detected by the IceCube Neutrino Observatory, as recently suggested by Buson et al. Although
C. Bellenghi +3 more
semanticscholar +1 more source
Kinematics of Parsec-scale Jets of Gamma-Ray Blazars at 43 GHz during 10 yr of the VLBA-BU-BLAZAR Program [PDF]
Astrophysical Journal Supplement Series, 2022 We analyze the parsec-scale jet kinematics from 2007 June to 2018 December of a sample of γ-ray bright blazars monitored roughly monthly with the Very Long Baseline Array (VLBA) at 43 GHz under the VLBA-BU-BLAZAR program.
Z. Weaver +9 more
semanticscholar +1 more source
Growing evidence for high-energy neutrinos originating in radio blazars [PDF]
Monthly notices of the Royal Astronomical Society, 2022 Evidence for bright radio blazars being high-energy neutrino sources was found in recent years. However, specifics of how and where these particles get produced still need to be determined.
A. Plavin +3 more
semanticscholar +1 more source
Characterizing Long-term Optical Variability Properties of γ-Ray-bright Blazars [PDF]
Astrophysical Journal, 2021 Optical observations of a sample of 12 γ-ray-bright blazars from four optical data archives—American Association of Variable Star Observers, Small and Moderate Aperture Research Telescope System, Catalina, and Steward Observatory—are compiled to create ...
G. Bhatta
semanticscholar +1 more source
The Central Engines of Fermi Blazars [PDF]
, 2021 We present a catalog of central engine properties, i.e., black hole mass (M BH) and accretion luminosity (L disk), for a sample of 1077 blazars detected with the Fermi Large Area Telescope.
V. Paliya +4 more
semanticscholar +1 more source
Frequency and Time Dependence of Linear Polarization in Turbulent Jets of Blazars [PDF]
Galaxies, 2021 Time-variable polarization is an extremely valuable observational tool to probe the dynamical physical conditions of blazar jets. Since 2008, we have been monitoring the flux and linear polarization of a sample of gamma-ray bright blazars at optical ...
A. Marscher, S. Jorstad
semanticscholar +1 more source
Classification of unassociated fermi-LAT sources [PDF]
ITM Web of Conferences, 2022 The Large Area Telescope (LAT) on board NASA’s Fermi Gamma-ray Space telescope has detected 5788 sources in the 4FGL catalogue. Among them, 271 have been associated to pulsars, 3436 to blazars, and 1782 remain unassociated sources.
Meng Qiyu
doaj +1 more source