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Related papers: Optical-radio positional offsets for active galact…

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Active Galactic Nuclei (AGN) outflows can regulate host galaxy evolution via AGN feedback. Ionised gas outflows have been linked to enhanced radio emission. In the first paper of this series, AGN detected with the International LOFAR…

We have combined a survey at 24 microns to 0.3 mJy with the Multiband Imaging Photometer (MIPS) on the Spitzer Space Telescope, a 20 cm A-array VLA survey covering 0.5 deg^2, and an existing 172 ks Chandra X-Ray Observatory exposure to…

(Abridged) Since its launch in October 2002, the INTEGRAL satellite has revolutionized our knowledge of the hard X-ray sky thanks to its unprecedented imaging capabilities and source detection positional accuracy above 20 keV. Nevertheless,…

We investigate the nature of low-luminosity radio-loud active galactic nuclei (RLAGN) selected from the LOFAR Two-metre Sky Survey (LoTSS) first data release (DR1). Using optical, mid-infrared, and radio data, we have conservatively…

Astrophysics of Galaxies · Physics 2024-03-01 J. Chilufya , M. J. Hardcastle , J. C. S. Pierce , J. H. Croston , B. Mingo , X. Zheng , R. D. Baldi , H. J. A. Röttgering

Offset active galactic nuclei (AGNs) are AGNs that are in ongoing galaxy mergers, which produce kinematic offsets in the AGNs relative to their host galaxies. Offset AGNs are also close relatives of dual AGNs. We conduct a systematic search…

Astrophysics of Galaxies · Physics 2015-06-19 Julia M. Comerford , Jenny E. Greene

Observational information on high-energy astrophysical neutrinos is being continuously collected by the IceCube observatory. However, the sources of neutrinos are still unknown. In this study, we use radio very-long-baseline interferometry…

High Energy Astrophysical Phenomena · Physics 2020-09-10 A. V. Plavin , Y. Y. Kovalev , Y. A. Kovalev , S. V. Troitsky

Very long baseline interferometry (VLBI) technique allows us to determine positions of thousands of radio sources using the absolute astrometry approach. I have investigated the impact of a selection of observing frequencies in a range from…

Instrumentation and Methods for Astrophysics · Physics 2024-05-14 Leonid Petrov

An essential part of the paradigm describing active galactic nuclei is the alignment between the radio jet and the associated rotation axis of the sub-pc sized accretion disks. Because of the small linear and angular scales involved, this…

In this pilot investigation, precise optical positions in the FK5 system are presented for a set of 16 compact extragalactic radio sources, which will be part of the future radio--optical reference frame. The 0.9 m KPNO and CTIO telescopes…

Astrophysics · Physics 2009-10-28 N. Zacharias , C. de Vegt , L. Winter , K. J. Johnston

We report the results of $g-$, $r-$, and $i-$dropout selections based on optical identifications of Very Large Array Sky Survey (VLASS) radio sources using the Hyper Suprime-Cam Subaru Strategic Program survey (HSC--SSP). By positional…

Based on a comparison of the SRG/eROSITA catalog of X-ray active stars and the Gaia catalog, a sample of 502 peculiar objects was obtained for which Gaia, on one hand, detects statistically significant values of parallax or proper motion…

High Energy Astrophysical Phenomena · Physics 2023-01-20 I. M. Khamitov , I. F. Bikmaev , M. R. Gilfanov , R. A. Sunyaev , P. S. Medvedev , M. A. Gorbachev , E. N. Irtuganov

The relationship between galaxies and their supermassive black holes (SMBHs) is an area of active research. One way to investigate this is to compare parsec-scale jets formed by SMBHs with the projected shape of their kiloparsec-scale host…

Astrophysics of Galaxies · Physics 2024-11-15 D. Fernández Gil , J. A. Hodgson , B. L'Huillier , J. Asorey , C. Saulder , K. Finner , M. J. Jee , D. Parkinson , F. Combes

Various studies have laid claim to finding an alignment of the polarization vectors or radio jets of active galactic nuclei (AGN) over large distances, but these results have proven controversial and so far, there is no clear explanation…

Context. A defining characteristic of active galactic nuclei (AGN) that distinguishes them from other astronomical sources is their stochastic variability, which is observable across the entire electromagnetic spectrum. Upcoming optical…

In the time domain, the radio sky in particular along the Galactic plane direction may vary significantly because of various energetic activities associated with stars, stellar and supermassive black holes. Using multi-epoch Very Large…

High Energy Astrophysical Phenomena · Physics 2022-01-12 Jun Yang , Yongjun Chen , Leonid I. Gurvits , Zsolt Paragi , Aiyuan Yang , Xiaolong Yang , Zhiqiang Shen

We present a milliarcsecond-resolution radio survey of 17 high-redshift (4 < z < 5.4) blazar candidates observed with the European Very Long Baseline Interferometry (VLBI) Network at 5 GHz. The primary objective of this study was to…

We report the results of a pilot study that searched for dual active galactic nuclei (AGN) in local ($z<$0.25) galaxies hosting double-peaked narrow emission lines in their optical spectra. We present high-resolution $L-$band (1.5 GHz or 18…

We obtained Keck/OSIRIS near-IR adaptive optics-assisted integral-field spectroscopy to probe the morphology and kinematics of the ionized gas in four velocity-offset active galactic nuclei (AGNs) from the Sloan Digital Sky Survey. These…

Astrophysics of Galaxies · Physics 2016-10-19 Francisco Müller-Sánchez , Julia M. Comerford , Daniel Stern , Fiona A. Harrison

Galaxy mergers are likely to play a role in triggering active galactic nuclei (AGN), but the conditions under which this process occurs are poorly understood. In Paper I, we constructed a sample of spatially offset X-ray AGN that represent…

Astrophysics of Galaxies · Physics 2017-04-12 R. Scott Barrows , Julia M. Comerford , Jenny E. Greene , David Pooley

We present a kinematic analysis based on the large Integral Field Spectroscopy (IFS) dataset of SDSS-IV MaNGA (10.000 galaxies). We have compiled a diverse sample of 594 unique Active Galactic Nuclei (AGN), identified through a variety of…

Astrophysics of Galaxies · Physics 2024-11-06 Marco Albán , Dominika Wylezalek , Julia M. Comerford , Jenny E. Greene , Rogemar A. Riffel
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