An Optical Overview of Blazars with LAMOST. I. Hunting Changing-look Blazars and New Redshift Estimates [PDF]
, 2021 The extragalactic γ-rays sky observed by the Fermi Large Area Telescope (LAT) is dominated by blazars. In the fourth release of the Fermi LAT Point Source Catalog (4FGL) are sources showing a multifrequency behavior similar to that of blazars but lacking
H. Peña-Herazo +8 more
semanticscholar +1 more source
The Spectral Energy Distributions for 4FGL Blazars
Astrophysical Journal Supplement Series, 2022 In this paper, the multiwavelength data from radio to X-ray bands for 2709 blazars in the 4FGL-DR3 catalog are compiled to calculate their spectral energy distributions using a parabolic equation log(νfν)=P1logν−P22+P3 .
J. H. Yang +21 more
semanticscholar +1 more source
Cosmic Neutrinos from Temporarily Gamma-suppressed Blazars
Astrophysical Journal Letters, 2021 Despite the uncovered association of a high-energy neutrino with the apparent flaring state of blazar TXS 0506+056 in 2017, the mechanisms leading to astrophysical particle acceleration and neutrino production are still uncertain.
E. Kun +5 more
semanticscholar +1 more source
A Comprehensive Power Spectral Density Analysis of Astronomical Time Series. I. The Fermi-LAT Gamma-Ray Light Curves of Selected Blazars [PDF]
Astrophysical Journal Supplement Series, 2020 We present the results of the Fermi-Large Area Telescope 10 yr long light curve (LC) modeling of selected blazars: six flat-spectrum radio quasars (FSRQs) and five BL Lacertae (BL Lacs), examined in 7, 10, and 14 day binning.
M. Tarnopolski +3 more
semanticscholar +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
Patterns in the Multiwavelength Behavior of Candidate Neutrino Blazars [PDF]
Astrophysical Journal, 2020 Motivated by the identification of the blazar TXS 0506+056 as the first promising high-energy neutrino counterpart candidate, we search for additional neutrino blazar candidates among the Fermi–Large Area Telescope detected blazars.
A. Franckowiak +10 more
semanticscholar +1 more source
Searches for IceCube neutrinos from blazar flares using correlations with gamma-ray lightcurves [PDF]
EPJ Web of Conferences, 2019 Blazars have long been considered as accelerator candidates for cosmic rays. In such a scenario, hadronic interactions in the jet would produce neutrinos and gamma rays.
Raab Christoph +1 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
Multiwavelength astrophysics of the blazar OJ 287 and the project MOMO
Astronomische Nachrichten, Volume 344, Issue 4, May 2023., 2023 Abstract We are carrying out the densest and longest multiyear, multiwavelength monitoring project of OJ 287 ever done. The project MOMO (Multiwavelength Observations and Modeling of OJ 287) covers wavelengths from the radio to the high‐energy regime. A few selected observations are simultaneous with those of the Event Horizon Telescope (EHT).
S. Komossa +21 more
wiley +1 more source