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Multi-messenger emission characteristics of blazars [PDF]
Frontiers in Astronomy and Space SciencesMulti-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 +10 more
doaj +2 more sources
A Model of Polarisation Rotations in Blazars from Kink Instabilities in Relativistic Jets
Galaxies, 2017 This paper presents a simple model of polarisation rotation in optically thin relativistic jets of blazars. The model is based on the development of helical (kink) mode of current-driven instability.
Krzysztof Nalewajko
exaly +3 more sources
Blazars at Very High Energies: Emission Modelling
Galaxies, 2022 Blazars are very broadband cosmic sources with spectra spanning over twenty orders of magnitude in frequency, down to the 100 MHz regime in the radio range, up to VHE at several tens of TeV.
Hélène Sol, A Zech
exaly +3 more sources
The RoboPol Program: Optical Polarimetric Monitoring of Blazars
Galaxies, 2019 After three years of polarimetric monitoring of blazars, the RoboPol project has uncovered several key characteristics of polarimetric rotations in the optical for these most variable sources.
D Blinov, Vasiliki Pavlidou
exaly +3 more sources
Source Count Distribution of Fermi LAT Gamma-Ray Blazars Using Novel Nonparametric Methods
UniverseWe utilized a sample from the Fermi-LAT 14-year Source Catalog by adjusting the flux detection threshold, enabling us to derive the intrinsic source count distribution dN/dF25 of extragalactic blazars using nonparametric, unbinned methods developed by ...
Houdun Zeng
exaly +3 more sources
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
The Astrophysical Journal, 2023 Recent works have developed samples of blazars from among the Fermi Large Area Telescope unassociated sources via machine-learning comparisons with known blazar samples. Continued analysis of these new blazars tests the predictions of the blazar sequence
Stephen Kerby, Abraham D. Falcone
doaj +1 more source
X-ray Flux and Spectral Variability of the TeV Blazars Mrk 421 and PKS 2155-304
Galaxies, 2020 We reviewed X-ray flux and spectral variability properties studied to date by various X-ray satellites for Mrk 421 and PKS 2155-304, which are TeV emitting blazars. Mrk 421 and PKS 2155-304 are the most X-ray luminous blazars in the northern and southern
Alok C. Gupta
doaj +1 more source
Exploring TeV Candidates of Fermi Blazars through Machine Learning
The Astrophysical Journal, 2023 In this work, we make use of a supervised machine-learning algorithm based on Logistic Regression (LR) to select TeV blazar candidates from the 4FGL-DR2/4LAC-DR2, 3FHL, 3HSP, and 2BIGB catalogs.
J. T. Zhu +5 more
doaj +1 more source
Probing Neutrino Production in Blazars by Millimeter VLBI
Galaxies, 2023 The advancement of neutrino observatories has sparked a surge in multi-messenger astronomy. Multiple neutrino associations among blazars are reported while neutrino production sites are located within their central (sub)parsecs.
Yuri Y. Kovalev +3 more
doaj +1 more source