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Related papers: Studies on slow radio transients

200 papers

We present the completed results of a high resolution radio imaging survey of all (~200) low-luminosity active galactic nuclei (LLAGNs) and AGNs in the Palomar Spectroscopic Sample. The high incidences of pc-scale radio nuclei, with…

Astrophysics · Physics 2009-11-10 Neil M. Nagar , Heino Falcke , Andrew S. Wilson

The cessation of AGN activity in radio galaxies leads to a remnant phase during which jets are no longer sustained, but lobes can be detected for a period of time before they fade away due to radiative and dynamical energy losses. The…

Astrophysics of Galaxies · Physics 2022-12-19 Sushant Dutta , Veeresh Singh , C. H. Ishwara Chandra , Yogesh Wadadekar , Abhijit Kayal

We present a study of the radio properties of the dominant early-type galaxies in 26 galaxy groups, the high-richness sub-sample of the Complete Local-volume Groups Sample (CLoGS). Combining new 610 MHz and 235 MHz observations of 21 groups…

Astrophysics of Galaxies · Physics 2018-07-31 Konstantinos Kolokythas , Ewan O'Sullivan , Somak Raychaudhury , Simona Giacintucci , Myriam Gitti , Arif Babul

We combine Chandra and XMM-Newton X-ray data from our previous papers with new X-ray observations and with Spitzer mid-infrared data in order to study the nature of the nuclei of radio galaxies and radio-loud quasars with z<1.0 from the…

Astrophysics of Galaxies · Physics 2015-05-13 M. J. Hardcastle , D. A. Evans , J. H. Croston

This paper presents a study of the redshift evolution of radio-loud active galactic nuclei (AGN) as a function of the properties of their galaxy hosts in the Bo\"otes field. To achieve this we match low-frequency radio sources from deep…

We are conducting a multi-wavelength (radio, optical, and X-ray) observational campaign to classify, morphologically and physically, a sample of 55 flat-spectrum radio sources dominated by structure on kpc-scales. This sample contains 22…

We study the cosmic evolution of radio sources out to $z \simeq 1.5$ using a GMRT 610 MHz survey covering $\sim$1.86 deg$^2$ of the ELAIS N1 field with a minimum/median rms noise 7.1/19.5\,$\mu$Jy / beam and an angular resolution of…

Astrophysics of Galaxies · Physics 2020-11-25 E. F. Ocran , A. R. Taylor , M. Vaccari , C. H. Ishwara-Chandra , I. Prandoni , M. Prescott , C. Mancuso

Gigahertz Peaked Spectrum (GPS) radio galaxies are generally thought to be the young counterparts of classical extended radio sources. Statistically complete samples of GPS sources are vital for studying the early evolution of radio-loud…

Astrophysics · Physics 2009-11-13 N. de Vries , I. A. G. Snellen , R. T. Schilizzi , M. D. Lehnert , M. N. Bremer

GH 10 is a broad-lined active galactic nucleus (AGN) energized by a black hole of mass 800,000 Solar masses. It was the only object detected by Greene et al. in their Very Large Array (VLA) survey of 19 low-mass AGNs discovered by Greene &…

Astrophysics · Physics 2009-11-13 J. M. Wrobel , J. E. Greene , L. C. Ho , J. S. Ulvestad

It is now established that the faint radio population is a mixture of star-forming galaxies and faint active galactic nuclei (AGNs), with the former dominating below S(1.4GHz) \sim 100 muJy and the latter at larger flux densities. The faint…

Astrophysics of Galaxies · Physics 2018-12-26 R. Ricci , I. Prandoni , H. R. De Ruiter , P. Parma

I review observational properties of low power radio loud AGN. High resolution VLBI observations allow the estimate of the jet velocity and orientation with respect to the line of sight and the determination of the Doppler factor. These…

Astrophysics · Physics 2009-04-14 G. Giovannini , M. Giroletti

We use deep multi-colour (UBVRIJK) images mostly taken in the framework of the ESO Deep Public Survey (DPS) to optically identify and derive photometric redshifts for a complete sample of 131 radio sources with S>0.4 mJy, observed at both…

Radio-loud active galactic nuclei (AGN) are among the most luminous objects in the Universe, emitting radiation from low-energy radio waves to high energy $\gamma$-rays. They are well known to exhibit flux variations at nearly all…

Astrophysics of Galaxies · Physics 2026-03-19 M. Reshma , C. S. Stalin , Amit Kumar Mandal , S. B. Gudennavar , Senorita Benedict , Prajwel Joseph

We study the morphology of the radio emission of giant radio galaxies (GRGs), a rare type of active galaxies, in order to find new clues for the reasons of their large size. Using radio images from two sky surveys at 1.4 GHz we quantified…

Astrophysics of Galaxies · Physics 2016-10-11 Elizabeth López Vázquez , Heinz Andernach

Narrow-line Seyfert 1 (NLS1) galaxies provide us with unique insights into the drivers of AGN activity under extreme conditions. Given their low black hole (BH) masses and near-Eddington accretion rates, they represent a class of galaxies…

High Energy Astrophysical Phenomena · Physics 2017-06-28 V. Karamanavis , E. Angelakis , S. Komossa , I. Myserlis , D. Blinov , J. A. Zensus

We study the radio properties of moderately obscured quasars over a range of redshifts to understand the role of radio activity in accretion using the Jansky Very Large Array (JVLA) at 6.0GHz and 1.4GHz. Our z~2.5 sample consists of…

Astrophysics of Galaxies · Physics 2016-08-31 Rachael M. Alexandroff , Nadia L. Zakamska , Sjoert van Velzen , Jenny E. Greene , Michael A. Strauss

In the last decade of Active Galactic Nuclei (AGN) monitoring programs, the Mets\"ahovi Radio Observatory detected multiple times seven powerful flaring narrow-line Seyfert 1 (NLS1) galaxies at 37 GHz. Several hypotheses have been proposed,…

Feedback by radio-loud active galactic nuclei (AGN) in galaxy groups is not fully understood. Open questions include the duty cycle of the AGN, the spatial extent of the radio lobes, the effect they have on the intragroup medium, and the…

Dual-Active Galactic Nuclei (AGN) are a natural consequence of the hierarchical structure formation scenario, and can provide an important test of various models for black hole growth. However, due to their rarity and difficulty to find at…

Astrophysics of Galaxies · Physics 2021-09-22 C. S. Mangat , J. P. McKean , R. Brilenkov , P. Hartley , H. R. Stacey , S. Vegetti , D. Wen

The host galaxies of powerful radio sources are ideal laboratories to study active galactic nuclei (AGN). The galaxies themselves are among the most massive systems in the universe, and are believed to harbor supermassive black holes…

Astrophysics · Physics 2009-11-07 W. de Vries , W. van Breugel , A. Quirrenbach