scholarly journals High-resolution VLA low radio frequency observations of the Perseus cluster: radio lobes, mini-halo, and bent-jet radio galaxies

2020 ◽  
Vol 499 (4) ◽  
pp. 5791-5805
Author(s):  
M Gendron-Marsolais ◽  
J Hlavacek-Larrondo ◽  
R J van Weeren ◽  
L Rudnick ◽  
T E Clarke ◽  
...  
Keyword(s):  
High Resolution ◽  
Dynamic Range ◽  
Galaxy Cluster ◽  
High Dynamic Range ◽  
Radio Galaxies ◽  
Radio Sources ◽  
Nearby Galaxy ◽  
Cluster Galaxy ◽  
Ngc 1275 ◽  
Perseus Cluster

ABSTRACT We present the first high-resolution 230–470 MHz map of the Perseus cluster obtained with the Karl G. Jansky Very Large Array. The high dynamic range and resolution achieved have allowed the identification of previously unknown structures in this nearby galaxy cluster. New hints of sub-structures appear in the inner radio lobes of the brightest cluster galaxy NGC 1275. The spurs of radio emission extending into the outer X-ray cavities, inflated by past nuclear outbursts, are seen for the first time at these frequencies, consistent with spectral aging. Beyond NGC 1275, we also analyse complex radio sources harboured in the cluster. Two new distinct, narrowly collimated jets are visible in IC 310, consistent with a highly projected narrow-angle tail radio galaxy infalling into the cluster. We show how this is in agreement with its blazar-like behaviour, implying that blazars and bent-jet radio galaxies are not mutually exclusive. We report the presence of filamentary structures across the entire tail of NGC 1265, including two new pairs of long filaments in the faintest bent extension of the tail. Such filaments have been seen in other cluster radio sources such as relics and radio lobes, indicating that there may be a fundamental connection between all these radio structures. We resolve the very narrow and straight tail of CR 15 without indication of double jets, so that the interpretation of such head–tail sources is yet unclear. Finally, we note that only the brightest western parts of the mini-halo remain, near NGC 1272 and its bent double jets.

scholarly journals High Resolution VLA Observations of Quasars with Distorted Radio Stucture

1982 ◽  
Vol 97 ◽  
pp. 39-40
Author(s):  
J. Stocke ◽  
W. Christiansen ◽  
J. Burns
Keyword(s):  
High Resolution ◽  
Dynamic Range ◽  
High Dynamic Range ◽  
Radio Galaxies ◽  
Cluster Membership ◽  
Double Structure ◽  
Structural Distortions ◽  
Extended Radio ◽  
High Dynamic ◽  
Structure Class

Most quasars with extended radio structures have the classical linear double structure (Class II) which is also characteristic of the most luminous radio galaxies. A very small fraction of quasars do, however, show deviations from the classical double structure which are similar to the distortions observed in some low luminosity radio galaxies, e.g., bent double sources. Among radio galaxies, structural distortions seem to be associated with membership in a cluster of galaxies. Indeed, Scott and Hintzen, 1978, have suggested that such distortions might be indicators of cluster membership for quasars as well. To test this hypothesis and examine the physics of distorted quasars, we have mapped the quasars 3C 270.1 and 3C 275.1 in both I and P using the VLA A-Array at 20 cm and 6 cm. Our high resolution (0.1 arc sec at 6 cm) and high dynamic range (200:1) observations demonstrate that the displaced components reported previously for these sources are indeed connected with the quasars themselves and, therefore, the distortions are not simply projection effects. We also report the discovery of a very narrow northwesterly pointing jet in the quasar 3C 275.1.

High-dynamic-range 21 cm JVLA observations of the Perseus Cluster

2018 ◽  
Vol 14 (S342) ◽  
pp. 53-54
Author(s):  
Charles L. H. Hull
Keyword(s):  
Dynamic Range ◽  
High Dynamic Range ◽  
Order Of Magnitude ◽  
High Dynamic ◽  
L Band ◽  
Ngc 1275 ◽  
Perseus Cluster

AbstractWe present 21 cm (L-band) JVLA observations of the Perseus Cluster, comprising data from all four array configurations. The resulting images are nearly an order of magnitude deeper than any other image made of NGC 1275 and its environs at this frequency.

scholarly journals VLA observations of 20 FR II radio sources at 8.4 GHz

2019 ◽  
Vol 364 (10) ◽  
Author(s):  
Ilias Fernini
Keyword(s):  
High Resolution ◽  
Hot Spots ◽  
Radio Galaxies ◽  
Class Ii ◽  
Outer Edge ◽  
Radio Sources ◽  
Large Sample ◽  
Contour Maps ◽  
Surrounding Environment

Abstract We report the last observational paper of hot spots for 20 Fanaroff-Riley class II (FR II) sources. These sources are part of a large sample of 98 FR II to study the unification scheme of FR II radio galaxies (RGs) and quasars (QSRs) using the hotspots (HSs) location and morphology. High-resolution VLA observations at 8.4 GHz were conducted for the whole sample. The investigation of HSs properties in FR II radio sources is essential for a better understanding of the dynamics related to the objects and their impact on the surrounding environment. HSs were classified into edged and recessed types, where the former is located at a radio lobe’s outer edge, and the latter is embedded within the lobe. The present sub-sample contains 12 RGs and 8 QSRs. Radio contour maps for each source were presented using the VLA in its A and B configurations. In total, we have identified 18 HSs for these 20 radio sources. The 12 RGs possess 8 edged HSs and 2 recessed HSs. The 8 QSRs possess 6 edged HSs and 2 recessed HSs. Out of the 14 edged HSs, RGs and QSRs possess $\sim57\%$∼57% and $\sim43\%$∼43%, respectively. A thorough morphological discussion of the 20 sources with their HSs is presented in the present work.

A high-dynamic-range and high-resolution projector with dual modulation

2009 ◽  
Author(s):  
Y. Kusakabe ◽  
M. Kanazawa ◽  
Y. Nojiri ◽  
M. Furuya ◽  
M. Yoshimura
Keyword(s):  
High Resolution ◽  
Dynamic Range ◽  
High Dynamic Range ◽  
High Dynamic

scholarly journals A high resolution, high dynamic range display for vision research

2010 ◽  
Vol 9 (8) ◽  
pp. 346-346 ◽  
Author(s):  
J. Ferwerda ◽  
S. Luka
Keyword(s):  
High Resolution ◽  
Vision Research ◽  
Dynamic Range ◽  
High Dynamic Range ◽  
High Dynamic

scholarly journals A radio halo surrounding the Brightest Cluster Galaxy in RXCJ0232.2–4420: a mini-halo in transition?

2019 ◽  
Vol 486 (1) ◽  
pp. L80-L84 ◽  
Author(s):  
Ruta Kale ◽  
Krishna M Shende ◽  
Viral Parekh
Keyword(s):  
Radio Source ◽  
Surface Brightness ◽  
Galaxy Cluster ◽  
Cosmic Ray ◽  
Radio Sources ◽  
Cluster Galaxy ◽  
X Ray ◽  
Radio Halo ◽  
The Galaxy ◽  
Radio Power

ABSTRACT Diffuse radio sources associated with the intra-cluster medium are direct probes of the cosmic ray electrons and magnetic fields. We report the discovery of a diffuse radio source in the galaxy cluster RXCJ0232.2–4420 (SPT-CL J0232–4421, z = 0.2836) using 606 MHz observations with the Giant Metrewave Radio Telescope. The diffuse radio source surrounds the Brightest Cluster Galaxy in the cluster-like typical radio mini-haloes. However the total extent of it is 550 × 800 kpc2, which is larger than mini-haloes and similar to that of radio haloes. The BCG itself is also a radio source with a marginally resolved core at 7 arcsec (30 kpc) resolution. We measure the 606 MHz flux density of the RH to be 52 ± 5 mJy. Assuming a spectral index of 1.3, the 1.4 GHz radio power is 4.5 × 1024 W Hz−1. The dynamical state of the cluster has been inferred to be 'relaxed’ and also as 'complex’, depending on the classification methods based on the morphology of the X-ray surface brightness. This system thus seems to be in the transition phase from a mini-halo to a radio halo.

scholarly journals Multi-Frequency Polarization Studies of Radio Galaxies

1982 ◽  
Vol 97 ◽  
pp. 53-54
Author(s):  
G. G. Pooley
Keyword(s):  
High Resolution ◽  
Radio Galaxies ◽  
Radio Sources ◽  
Frequency Range ◽  
Extragalactic Radio Sources ◽  
High Resolution Mapping ◽  
New Instrument ◽  
Resolution Mapping ◽  
Polarization Studies ◽  
The One

This is a brief report on some of the work in progress at Cambridge, with emphasis on studies of extragalactic radio sources using the One-mile and 5-km telescopes; together with the 6C survey and a new instrument now being commisioned at 151 MHz, we have a frequency range of 100:1 available for high-resolution mapping. The 6C survey has resulted in the discovery of a number of giant radio galaxies, most notably NGC 6251. At 151 MHz, the beautiful jet is not prominent; we have mapped it with the One-mile and 5-km instruments and a paper (by Saunders et al.) will shortly appear in Monthly Notices. Dr Willis will speak later on the structure of this source.

scholarly journals The Evolution of Compact Steep-Spectrum Sources

1998 ◽  
Vol 164 ◽  
pp. 295-296
Author(s):  
S. Jeyakumar ◽  
D. J. Saikia
Keyword(s):  
High Resolution ◽  
Radio Galaxies ◽  
Radio Sources ◽  
Radio Data ◽  
Asymmetric Environment

AbstractWe used our high-resolution radio images made with VLA of a large number of compact steep-spectrum (CSS) sources selected from well-defined samples of radio sources and the radio data of these samples to explore the evolution of CSSs with time. We suggest that the majority of CSSs are likely to be young sources advancing outwards through an asymmetric inhomogeneous environment to form the larger ones. We examine the symmetry parameters of both CSSs and larger sources and compare these with both analytical and numerical estimates of propagation of jets through an asymmetric environment. We also examine the consistency of CSSs with the unified scheme for radio galaxies and quasars.

Sign in / Sign up

Export Citation Format

Share Document