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相关论文: Constraining the evolution of young radio-loud AGN

200 篇论文

We present a multi-wavelength study into the nature of faint radio sources in a deep radio image with the Giant Meterwave Radio Telescope at 612\,MHz covering 1.2 deg$^2$ of the ELAIS N1 region. We detect 2800 sources above…

星系天体物理 · 物理学 2017-04-12 E. F. Ocran , A. R. Taylor , M. Vaccari , D. A. Green

We discovered an X-ray cluster in a recent pointed Chandra observation of the radio-loud compact-steep-spectrum source 1321+045 at the redshift of 0.263. 1321+045 is part of larger survey which aims to study the X-rays properties of weak…

星系天体物理 · 物理学 2013-11-18 Maciej Ceglowski , Magdalena Kunert-Bajraszewska , A. Siemiginowska , A. Labiano , M. Guainazzi

The vast majority of extragalactic compact continuum radio sources are associated with star formation or jets from (super)massive black holes and, as such, are more likely to be found in association with starburst galaxies or early-type…

高能天体物理现象 · 物理学 2023-12-20 D. Vohl , H. K. Vedantham , J. W. T. Hessels , C. G. Bassa , D. O. Cook , D. L. Kaplan , T. W. Shimwell , C. Zhang

We positionally match the 6 cm GB6, 20 cm FIRST and NVSS, and 92 cm WENSS radio catalogs and find 16,500 matches in ~3,000 deg2 of sky. Using this unified radio database, we construct radio "color-magnitude-morphology" diagrams and find…

We report the results of multifrequency-VLBI observations of GHz-Peaked-Spectrum (GPS) radio sources. The VLBI structure and component spectra of some GPS sources are presented. Our VLBI results show that about 80% of the GPS galaxies…

宇宙学与河外天体物理 · 物理学 2010-05-20 X. Liu , H. -G Song , L. Cui

In the past decade, high sensitivity radio surveys have revealed that the local radio AGN population is dominated by moderate-to-low power sources with emission that is compact on galaxy scales. High-excitation radio galaxies (HERGs) with…

星系天体物理 · 物理学 2020-03-04 Jonathon C. S. Pierce , Clive N. Tadhunter , Raffaella Morganti

The faint radio-source population includes sources dominated both by star formation and active galactic nuclei (AGN), encoding the evolution of activity in the Universe. To investigate its nature, we probabilistically classified 4,471 radio…

Extended radio emission detected around a sample of GHz Peaked Spectrum (GPS) radio sources is discussed. Evidence for extended emission which is related to the GPS source is found in 6 objects out of 33. Three objects are associated with…

天体物理学 · 物理学 2009-11-11 C. Stanghellini , C. P. O'Dea , D. Dallacasa , P. Cassaro , S. A. Baum , R. Fanti , C. Fanti

We use highly spectroscopically complete observations of the radio sources from the VLA 1.4 GHz survey of the HDF-N region to study the faint radio galaxy population and its evolution. We spectrally classify the sources into four spectral…

天体物理学 · 物理学 2011-02-11 A. J. Barger , L. L. Cowie , W. -H. Wang

They are weak, they are small, and they are often overlooked, but they are numerous and an ubiquitous sign of accreting black holes: compact radio cores and jets in low-power AGN. Here I summarize our work concerning these radio cores and…

天体物理学 · 物理学 2007-05-23 Heino Falcke

This work studies the correlation among environmental density and radio AGN presence up to $z = 2$. Using data from the photometric COSMOS survey and its radio 1.4 GHz follow-up (VLA-COSMOS), a sample of radio AGNs has been defined. The…

星系天体物理 · 物理学 2016-09-09 Nicola Malavasi , Sandro Bardelli , Paolo Ciliegi , Olivier Ilbert , Lucia Pozzetti , Elena Zucca

In this paper we analyse whether `giant' radio galaxies (GRGs) differ from `normal'-size galaxies (NSGs) except for the linear extent of their radio structure. We compare a number of properties of GRGs with the corresponding properties of…

天体物理学 · 物理学 2009-11-11 J. Machalski , M. Jamrozy

Kinematic and spectral studies are improving our knowledge of the age distribution in compact radio sources, providing evidence that small sources are generally very young. The properties of jets in objects spanning the size range from a…

天体物理学 · 物理学 2007-07-25 M. Giroletti

Following previous work, we further confirm that the cosmic evolution of steep-spectrum radio-loud AGNs (active galactic nuclei) can be reproduced by a simple combination of density evolution (DE) and luminosity evolution (LE). This mixture…

高能天体物理现象 · 物理学 2018-10-31 Zunli Yuan , Jiancheng Wang , Ming Zhou , Longhua Qin , Jirong Mao

This paper analyses the radio properties of a subsample of optically obscured (R>25.5) galaxies observed at 24um by the Spitzer Space Telescope within the First Look Survey. 96 F[24um]>0.35 mJy objects out of 510 are found to have a radio…

天体物理学 · 物理学 2009-11-13 M. Magliocchetti , P. Andreani , M. A. Zwaan

At bright radio powers ($P_{\rm 1.4 GHz} > 10^{25}$ W/Hz) the space density of the most powerful sources peaks at higher redshift than that of their weaker counterparts. This paper establishes whether this luminosity-dependent evolution…

星系天体物理 · 物理学 2015-09-16 E. E. Rigby , J. Argyle , P. N. Best , D. Rosario , H. J. A. Röttgering

We present a study of the extended radio emission in a sample of 8434 low redshift (z < 0.35) broad line active galactic nuclei (AGN) from the Sloan Digital Sky Survey (SDSS). To calculate the jet and lobe contributions to the total radio…

宇宙学与河外天体物理 · 物理学 2015-05-20 Stephen E. Rafter , D. Michael Crenshaw , Paul J. Wiita

We combine deep optical and radio data, from the Hyper Suprime-Cam and the Low-Frequency Array (LOFAR) respectively, to study 78 radio AGN in nearby (z<0.5) dwarf galaxies. Comparison to a control sample, matched in stellar mass and…

We discuss the properties of compact nuclear radio components in Seyfert galaxies from the extended 12-micron AGN sample of Rush et al.(1993). Our main results can be summarised as follows. Type 1 and type 2 Seyferts produce compact radio…

天体物理学 · 物理学 2009-11-06 Andy Thean , Alan Pedlar , Marek J. Kukula , Stefi A. Baum , Christopher P. O'Dea

The study on the dynamic evolution of young supernova remnants (SNRs) is an important way to understand the density structure of the progenitor's circumstellar medium. We have reported the acceleration or deceleration, proper motion and…

星系天体物理 · 物理学 2022-12-14 Xianhuan Lei , Hui Zhu , Haiyan Zhang , Wenwu Tian
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