186 citations · 2.1k across the 43 of their papers we have counts for
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Blazars as a Potential Origin of the KM3-230213A Event
The KM3NeT Collaboration
The KM3NeT collaboration has reported the detection of the highest energy neutrino event observed to date. The energy of the event is of the order of 220 PeV hinting towards a neut…
Revealing a ribbon-like jet in OJ 287 with RadioAstron
E. Traianou, J. L. Gomez, I. Cho +17
We present space-based very long baseline interferometry observations of the BL Lac type object OJ 287 taken with RadioAstron at 22 GHz on April 25, 2016, in conjunction with a gro…
Characterizing Candidate Blazar Counterparts of the Ultra-High-Energy Event KM3-230213A
KM3NeT Collaboration, MessMapp Group, LAT Collaboration +13
High-energy astrophysical neutrinos serve as crucial messengers for understanding hadronic acceleration processes and identifying the origins of cosmic rays, with blazars among the…
Multi-band Cross-correlated Radio Variability of the Blazar 3C 279
Krishna Mohana A, Alok C. Gupta, Alan P. Marscher +18
We present the results of our study of cross-correlations between long-term multi-band observations of the radio variability of the blazar 3C 279. More than a decade (2008-2022) of…
Filamentary structures as the origin of blazar jet radio variability
Antonio Fuentes, José L. Gómez, José M. Martí +22
Supermassive black holes at the centre of active galactic nuclei power some of the most luminous objects in the Universe. Typically, very long baseline interferometric (VLBI) obser…
Probing neutrino production in blazars by millimeter VLBI
Y. Y. Kovalev, A. V. Plavin, A. B. Pushkarev +1
The advancement of neutrino observatories has sparked a surge in multi-messenger astronomy. Multiple neutrino associations among blazars are reported while neutrino production site…
Key Science Goals for the Next-Generation Event Horizon Telescope
Michael D. Johnson, Kazunori Akiyama, Lindy Blackburn +42
The Event Horizon Telescope (EHT) has led to the first images of a supermassive black hole, revealing the central compact objects in the elliptical galaxy M87 and the Milky Way. Pr…
MOJAVE XXI. Decade-long linear polarization variability in AGN jets at parsec scales
D. I. Zobnina, H. D. Aller, M. F. Aller +6
Using stacking of images obtained at different epochs, we studied the variability properties of linear polarization of active galactic nucleus (AGN) jets on parsec-scales. Our samp…
Growing evidence for high-energy neutrinos originating in radio blazars
A. V. Plavin, Y. Y. Kovalev, Y. A. Kovalev +1
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 de…
MOJAVE. XX. Persistent Linear Polarization Structure in Parsec-scale AGN Jets
A. B. Pushkarev, M. F. Aller, H. D. Aller +6
We analysed the parsec-scale linear polarization properties of 436 active galactic nuclei (AGN) based on 15 GHz polarimetric Very Long Baseline Array (VLBA) observations. We presen…
Unravelling the Innermost Jet Structure of OJ 287 with the First GMVA+ALMA Observations
Guang-Yao Zhao, Jose L. Gomez, Antonio Fuentes +33
We present the first very-long-baseline interferometric (VLBI) observations of the blazar OJ287 carried out jointly with the Global Millimeter VLBI Array (GMVA) and the phased Atac…
Direction of Parsec-Scales Jets for 9220 Active Galactic Nuclei
A. V. Plavin, Y. Y. Kovalev, A. B. Pushkarev
The direction of parsec-scale jets in active galactic nuclei (AGNs) is essential information for many astrophysical and astrometric studies, including linear polarization and magne…
MOJAVE XIX: Brightness Temperatures and Intrinsic Properties of Blazar Jets
D. C. Homan, M. H. Cohen, T. Hovatta +7
We present multi-epoch, parsec-scale core brightness temperature observations of 447 AGN jets from the MOJAVE and 2cm Survey programs at 15 GHz from 1994 to 2019. The brightness te…
MOJAVE: XVIII. Kinematics and Inner Jet Evolution of Bright Radio-Loud Active Galaxies
M. L. Lister, D. C. Homan, K. I. Kellermann +4
We have analyzed the parsec-scale jet kinematics of 447 bright radio-loud AGN, based on 15 GHz VLBA data obtained between 1994 August 31 and 2019 August 4. We present new total int…
Parsec-scale Faraday rotation and polarization of 20 active galactic nuclei jets
E. V. Kravchenko, Y. Y. Kovalev, K. V. Sokolovsky
We perform polarimetry analysis of 20 active galactic nuclei (AGN) jets using the Very Long Baseline Array (VLBA) at 1.4, 1.6, 2.2, 2.4, 4.6, 5.0, 8.1, 8.4, and 15.4 GHz. The study…
Probing the innermost regions of AGN jets and their magnetic fields with RadioAstron. I. Imaging BL Lacertae at 21 microarcsecond resolution
José L. Gómez, Andrei P. Lobanov, Gabriele Bruni +10
We present the first polarimetric space VLBI imaging observations at 22 GHz. BL Lacertae was observed in 2013 November 10 with the RadioAstron space VLBI mission, including a groun…
MOJAVE XII: Acceleration and Collimation of Blazar Jets on Parsec Scales
D. C. Homan, M. L. Lister, Y. Y. Kovalev +5
We report on the acceleration properties of 329 features in 95 blazar jets from the MOJAVE VLBA program. Nearly half the features and three-quarters of the jets show significant ch…
Studies of the Jet in BL Lacertae I. Recollimation Shock and Moving Emission Features
M. H. Cohen, D. L. Meier, T. G. Arshakian +7
Parsec-scale VLBA images of BL Lac at 15 GHz show that the jet contains a permanent quasi-stationary emission feature 0.26 mas (0.34 pc projected) from the core, along with numerou…
Analyzing polarization swings in 3C 279
S. Kiehlmann, T. Savolainen, S. G. Jorstad +53
Quasar 3C 279 is known to exhibit episodes of optical polarization angle rotation. We present new, well-sampled optical polarization data for 3C 279 and introduce a method to disti…
Discovery of a new TeV gamma-ray source: VER J0521+211
VERITAS Collaboration, S. Archambault, T. Arlen +83
We report the detection of a new TeV gamma-ray source, VER J0521+211, based on observations made with the VERITAS imaging atmospheric Cherenkov telescope array. These observations…
The first Fermi multifrequency campaign on BL Lacertae: characterizing the low-activity state of the eponymous blazar
A. A. Abdo
We report on observations of BL Lacertae during the first 18 months of Fermi-LAT science operations and present results from a 48-day multifrequency coordinated campaign from 2008…
Multiwavelength monitoring of the enigmatic Narrow-Line Seyfert 1 PMN J0948+0022 in March-July 2009
LAT Collaboration, E. Angelakis, C. Bailyn +39
Following the recent discovery of gamma rays from the radio-loud narrow-line Seyfert 1 galaxy PMN J0948+0022 (z=0.5846), we started a multiwavelength campaign from radio to gamma r…
Spectral Analysis of the Accretion Flow in NGC 1052 with Suzaku
L. W. Brenneman, K. A. Weaver, M. Kadler +10
We present an analysis of the 101 ks, 2007 Suzaku spectrum of the LINER galaxy NGC 1052. The 0.5-10 keV continuum is well-modeled by a power-law modified by Galactic and intrinsic…
Multiwavelength Observations of Markarian 421 in 2005 - 2006
D. Horan, V. A. Acciari, S. M. Bradbury +71
Since September 2005, the Whipple 10m Gamma-ray Telescope has been operated primarily as a blazar monitor. The five Northern Hemisphere blazars that have already been detected at t…