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Related papers: VaDAR: Varstrometry for Dual AGN using Radio inter…

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Type II quasars are luminous AGNs whose central engines and broad-line regions are obscured by intervening material; such objects only recently have been discovered in appreciable numbers. We study the multiwavelength properties of 291 type…

Gaia data release 2 (DR2) provides the best non-rotating optical frame aligned with the radio frame (ICRF) thanks to the inclusion of about half-million quasars in the 5-parameter astrometric solution. Given their crucial diagnostic role…

Astrophysics of Galaxies · Physics 2018-10-25 Shilong Liao , Beatric Bucciarelli , Zhaoxiang Qi , Sufen Guo , Zihuang Cao , Zhenghong Tang

In this work, we use 8 years of deep near-infrared imaging to select and study a new set of 601 active galaxies identified through long-term near-infrared (NIR) variability in the UKIDSS Ultra Deep Survey (UDS). These objects are compared…

Astrophysics of Galaxies · Physics 2024-05-24 K. Green , E. Elmer , D. T. Maltby , O. Almaini , M. Merrifield , W. G. Hartley

BL Lac Objects (BL Lacs) and Flat Spectrum Radio Quasars (FSRQs) are radio-loud active galaxies (AGNs) whose jets are seen at a small viewing angle (blazars), while Misaligned Active Galactic Nuclei (MAGNs) are mainly radiogalaxies of type…

High Energy Astrophysical Phenomena · Physics 2018-08-20 G. Chiaro , M. Meyer , N. Alvarez Crespo , R. J. Britto , J. P. Marais , B. van Soelen , D. Salvetti , G. La Mura , D. J Thompson

Since the discovery of active galactic nuclei (AGN) and their subclasses, a unification scheme of AGN has been long sought. Orientation-based unified models predict that some of the diversity within AGN subclasses can be explained by the…

Astrophysics of Galaxies · Physics 2020-01-08 Suk Yee Yong , Rachel L. Webster , Anthea L. King , Nicholas F. Bate , Kathleen Labrie , Matthew J. O'Dowd

Astrometric noise in excess of parallax and proper motion could be a signature of orbital wobble of individual components in binary star systems. The combination of X-ray selection with astrometric noise can then be a powerful tool for…

High Energy Astrophysical Phenomena · Physics 2022-01-05 Poshak Gandhi , David A. H. Buckley , Phil Charles , Simon Hodgkin , Simone Scaringi , Christian Knigge , Anjali Rao

We use mid-infrared variability in galaxies to search for active galactic nuclei (AGN) in the local universe. We use a sample of 10,220 galaxies from the Mapping Nearby Galaxies at APO (MaNGA) survey, part of the Sloan Digital Sky Survey…

Astrophysics of Galaxies · Physics 2024-12-09 Aashay Pai , Michael R. Blanton , John Moustakas

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…

We present high resolution (arcsecond or better) observations made with the Karl G. Jansky Very Large Array of 123 radio-loud quasars with redshifts in the range $2.5 \leq z \leq 5.28$ that form a complete flux limited sample ($\geq 70$ mJy…

Astrophysics of Galaxies · Physics 2014-06-19 Doug B. Gobeille , John F. C. Wardle , C. C. Cheung

Active galactic nuclei (AGN) are some of the most powerful objects in the Universe. For this reason, they can be observed up to high redshifts (z), giving valuable insights into the evolution of our Universe. However, high-z AGN are too…

High Energy Astrophysical Phenomena · Physics 2025-05-14 Alysa Rogers , Daniel Schwartz , Cristiana Spingola , Anna Barnacka

We present multi-frequency and high-resolution studies of a sample of 24 radio transients sources discovered by comparing the NRAO VLA Sky Survey (NVSS) and Very Large Array Sky Survey (VLASS) surveys. All of them are characterized by a…

Astrophysics of Galaxies · Physics 2024-12-11 M. Kunert-Bajraszewska , A. Krauze , A. E. Kimball , L. Stawarz , P. Kharb , D. Stern , K. Mooley , K. Nyland , D. Koziel-Wierzbowska

We present the results of spectroscopic observations of host galaxies of eleven candidate giant radio galaxies (GRGs), powered by active galactic nuclei (AGNs), conducted with the 2-m Himalayan Chandra Telescope (HCT). The primary aim of…

Astrophysics of Galaxies · Physics 2025-02-11 Sagar Sethi , Pratik Dabhade , K. G. Biju , C. S. Stalin , Marek Jamrozy

A global understanding of Active Galactic Nuclei (AGN) and their host galaxies hinges on completing a census of AGN activity without selection biases down to the low-luminosity regime. Toward that goal, we identify AGN within faint radio…

Astrophysics of Galaxies · Physics 2020-10-14 Stacey Alberts , Wiphu Rujopakarn , George Rieke , Preshanth Jagannathan , Kristina Nyland

The energy released by active galactic nuclei (AGNs) is considered to have a profound impact on the cold gas properties of their host galaxies, potentially heating or removing the gas and further suppressing star formation. To understand…

Astrophysics of Galaxies · Physics 2026-01-27 Yuhan Wen , Ran Wang , Luis C. Ho , Jinyi Shangguan , Ezequiel Treister , Guodong Li , Franz E. Bauer

We identified Active Galactic Nuclei (AGN) candidates as counterparts to unidentified gamma-ray sources (UGS) from the Fermi-LAT Fourth Source Catalogue at lower Galactic latitudes. Our methodology is based on the use of near- and…

Studies show that both radio jets from the active galactic nuclei (AGN) and the star formation (SF) activity in quasar host galaxies contribute to the quasar radio emission; yet their relative contributions across the population remain…

We present radio observations of the galaxy merger remnant Mrk 212 with the Karl G. Jansky Very Large Array (VLA) and the upgraded Giant Meter Radio Telescope (uGMRT). Mrk 212 has two previously known radio sources associated with the two…

Astrophysics of Galaxies · Physics 2020-11-11 K. Rubinur , P. Kharb , M. Das , P. T Rahna , M. Honey , A. Paswan , S. Vaddi , J. Murthy

Active Galactic Nuclei (AGN) can be probed by at different regions of the electromagnetic spectrum: e.g., radio observations reveal the nature of their relativistic jets and their magnetic fields, and complementarily, X-ray observations…

The Cherenkov Telescope Array Observatory (CTAO) will enable detailed studies of Active Galactic Nuclei (AGN) in the very-high-energy (VHE) regime, as the next-generation ground-based gamma-ray observatory, designed to enhance sensitivity…

Variability is a property shared by virtually all active galactic nuclei (AGNs), and was adopted as a criterion for their selection using data from multi epoch surveys. Low Luminosity AGNs (LLAGNs) are contaminated by the light of their…

Astrophysics · Physics 2009-11-13 D. Trevese , K. Boutsia , F. Vagnetti , E. Cappellaro , S. Puccetti