Results 1 to 10 of about 2,377,761 (195)
Reconnection-driven State Transitions in Flat Spectrum Radio Quasars
The Astrophysical JournalWe extend the work of Roychowdhury on skewness variations of the logarithmic flux, driven by large GeV flares in flat spectrum radio quasars (FSRQs), to a sample of 18 FSRQs.
Agniva Roychowdhury
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The “Blazar Sequence” in the TeV Band
The Astrophysical Journal, 2023 The “blazar sequence” has been proposed for more than 20 yr, yet its nature is still unclear. In this work, for the first time we expand this topic to the TeV band by using a sample of 58 TeV blazars, including 48 blazars in the quiescent state and 21 ...
Zhihao Ouyang +9 more
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Identification of the OGLE Blazars behind the Large and Small Magellanic Clouds
Galaxies, 2017 We report the selection of blazar candidates behind the Large and Small Magellanic Clouds. Both flat spectrum radio quasar and BL Lacreate objects were selected based on the long-term, multi-colour Optical Gravitational Lensing Experiment photometric ...
Natalia Żywucka +6 more
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Correlation between Emission-line Luminosity and Gamma-Ray Dominance in the Blazar 3C 279
The Astrophysical Journal, 2023 Despite numerous studies, the origin of the γ -ray emission from blazars is still debated, in particular whether it is produced by leptonic or hadronic processes.
A. Dmytriiev +2 more
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Propagation of Very-high-energy γ-Rays from Distant Blazars
The Astrophysical Journal, 2023 We rederive the possible dependence of the redshift with a very-high-energy (VHE) γ -ray photon index. The results suggest that the universe to VHE γ -rays is becoming more transparent than expected.
L. J. Dong, Y. G. Zheng, S. J. Kang
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Classification of Fermi BCUs Using Machine Learning
The Astrophysical Journal, 2023 The Fermi Large Area Telescope (LAT) has detected 6659 γ -ray sources in the incremental version (4FGL-DR3, for Data Release 3) of the fourth Fermi-LAT catalog of γ -ray sources and 3743 of them are blazars, including 1517 blazar candidates of uncertain ...
Pei-yu Xiao +12 more
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Intra-Day Variability Observations of Two Dozens of Blazars at 4.8 GHz
Universe, 2021 Two dozens of radio loud active galactic nuclei (AGNs) have been observed with Urumqi 25 m radio telescope in order to search for intra-day variability (IDV).
Xiang Liu +6 more
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The Astrophysical JournalHigh-energy blazar light curves, in X-rays and beyond, have historically preferred a log-normal flux distribution, signifying multiplicative processes either in the jet itself or due to connection(s) with accretion.
Agniva Roychowdhury
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Narrow-Line Seyfert 1 Galaxies With Absorbed Jets–Insights From Radio Spectral Index Maps
Frontiers in Astronomy and Space Sciences, 2021 Narrow-line Seyfert 1 (NLS1) galaxies are active galactic nuclei (AGN) believed to be in the early stages of their evolution. A fraction of them have been found to host relativistic jets.
Emilia Järvelä +3 more
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The relationship between the emission line, continuum luminosity, and Baldwin effect in blazars
Astronomy & AstrophysicsAims. This study investigates the relationship between the Mg II λ2798 Å emission line and the 3000 Å continuum luminosity, as well as the Baldwin effect, in a sample of 40’,685 radio-quiet (RQ) quasars and 441 flat spectrum radio quasars (FSRQs ...
Patiño-Álvarez Víctor M. +5 more
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