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481
Observations of low and intermediate-frequency-peaked BL Lacs above 100 GeV with VERITAS
Published 2013-12-01“…Most of the ~ 50 blazars detected to date at TeV energies (E > 0.1 TeV) are high-frequency-peaked BL Lacs (HBLs). …”
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482
Multiwavelength Observations of 6 BL Lac Objects in 2008-2012
Published 2013-12-01“…These results support the conclusion that for many flares in blazars the region of the γ-ray and optical emission is located in the vicinity or downstream of the mm-wave VLBI core.…”
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483
Cosmic-void observations reconciled with primordial magnetogenesis
Published 2023-11-01“…However, accepted models of turbulent magnetohydrodynamic decay predict that the present-day strength of fields originally generated at the electroweak phase transition (EWPT) without parity violation would be too low to explain the observed scattering of γ-rays from TeV blazars. Here, we propose that the decay is mediated by magnetic reconnection and conserves the mean square fluctuation level of magnetic helicity. …”
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484
Cosmic-void observations reconciled with primordial magnetogenesis
Published 2022“…However, accepted models of turbulent magnetohydrodynamic decay predict that the present-day strength of fields originally generated at the electroweak phase transition (EWPT) without parity violation would be too low to explain the observed scattering of γ-rays from TeV blazars. Here, we propose that the decay is mediated by magnetic reconnection and conserves the mean square fluctuation level of magnetic helicity. …”
Internet publication -
485
The Gamma-ray window to intergalactic magnetism
Published 2021“…Because the charged component of the cascade is sensitive to magnetic fields, gamma-ray observations of distant objects such as blazars can be used to constrain IGMF properties. …”
Journal article -
486
The Gamma-ray Window to Intergalactic Magnetism
Published 2021-07-01“…Because the charged component of the cascade is sensitive to magnetic fields, gamma-ray observations of distant objects such as blazars can be used to constrain IGMF properties. …”
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487
Very high-energy gamma-ray follow-up program using neutrino triggers from IceCube
Published 2017“…The use of neutrino-triggered alerts thus aims at increasing the availability of simultaneous multi-messenger data during potential neutrino flaring activity, which can increase the discovery potential and constrain the phenomenological interpretation of the high-energy emission of selected source classes (e.g. blazars). The requirements of a fast and stable online analysis of potential neutrino signals and its operation are presented, along with first results of the program operating between 14 March 2012 and 31 December 2015.…”
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488
Very high-energy gamma-ray follow-up program using neutrino triggers from IceCube
Published 2016“…The use of neutrino-triggered alerts thus aims at increasing the availability of simultaneous multi-messenger data during potential neutrino flaring activity, which can increase the discovery potential and constrain the phenomenological interpretation of the high-energy emission of selected source classes (e.g. blazars). The requirements of a fast and stable online analysis of potential neutrino signals and its operation are presented, along with first results of the program operating between 14 March 2012 and 31 December 2015.…”
Journal article -
489
Some contributions of MAGIC to the physics ofcosmic rays
Published 2013-06-01“…Sources of high relevance for the study of very high energy hadronic interactions are active galactic nuclei, as blazars and radio galaxies. MAGIC has detectedabout fifty such extragalactic objects; we will present some where theemission is explained with accelerated hadrons in interaction with ambient photons. …”
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490
The local-filament pattern in the anomalous transparency of the Universe for energetic gamma rays
Published 2021-03-01“…Here, we consider the distribution in the sky of these apparently anomalous objects, selected in two very different approaches: the study of unphysical hardenings at distance-dependent energies in deabsorbed spectra of TeV blazars, and the observation of ultra-high-energy air showers from the directions of BL Lac type objects. …”
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491
Cosmic-void observations reconciled with primordial magnetogenesis
Published 2023“…However, accepted models of turbulent magnetohydrodynamic decay predict that the present-day strength of fields originally generated at the electroweak phase transition (EWPT) without parity violation would be too low to explain the observed scattering of <em>γ</em>-rays from TeV blazars. Here, we propose that the decay is mediated by magnetic reconnection and conserves the mean square fluctuation level of magnetic helicity. …”
Journal article -
492
Measurement of the Multi-TeV gamma-ray Flare-Spectra of Markarian 421 and Markarian 501
Published 1998“…The differences in TeV energy spectra of gamma-ray blazars reflect both the physics of the gamma-ray production mechanism and possibly differential absorption effects at the source or in the intergalactic medium. …”
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493
Sample Variance in Cosmological Observations with a Narrow Field of View
Published 2023-01-01“…We present a new method for accurately computing the sample variance and apply our method to the recent observations of the warm–hot intergalactic medium (WHIM) based on spectroscopic measurements of blazars. We find that the sample variances in these surveys are significantly larger than the quoted measurement errors; for example, the cosmic mean baryon density contained in the WHIM could be lower by 54% at 1 σ fluctuation than estimated in one observation. …”
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494
The Origin of Matter at the Base of Relativistic Jets in Active Galactic Nuclei
Published 2020-07-01“…The generation of relativistic jets in active sources such as blazars is a complex problem with many aspects, most of them still not fully understood. …”
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495
FACT — STATUS AND FIRST RESULTS
Published 2014-06-01“…Apart from commissioning and calibration measurements, it has already started regular operation, where the main goal is to do long-term monitoring of bright TeV blazars. In June 2012, a flare of Mrk 501 was observed. …”
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496
Electron-positron cascade in magnetospheres of spinning black holes
Published 2018“…These jets could be from active galactic nuclei, blazars, quasars, microquasars, radioactive galaxies, and other systems that host Kerr BHs. …”
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497
X-Ray Flares in the Long-term Light Curve of Low-luminosity Active Galactic Nucleus M81*
Published 2023-01-01“…The variation in the values of the jet parameters during the different states is shown and compared with high-synchrotron peaked blazars.…”
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498
AGILE Highlights after Six Years in Orbit
Published 2014-12-01“…Thanks to its sky monitoring capability and fast ground segment alert system, AGILE detected many Galactic and extragalactic sources: among other results AGILE discovered gamma-ray emission from the microquasar Cygnus X-3, detected many bright blazars, discovered several new gamma-ray pulsars, and discovered emission up to 100 MeV from Terrestrial Gamma-Ray Flashes. …”
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499
Radio Galaxies at TeV Energies
Published 2022-04-01“…Unlike blazars, radio galaxies have jets that are misaligned relative to our line-of-sight. …”
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500
Constraints on the Intergalactic Magnetic Field Strength from γ-Ray Observations of GRB 221009A
Published 2023-01-01“…Though this limit may not be as strong as the limit from blazars, it serves as an independent constraint on IGMF from a new class of TeV sources.…”
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