Extreme jet distortions in low-z radio galaxies

2018 ◽  
Vol 14 (A30) ◽  
pp. 61-65
Author(s):  
Mark Birkinshaw ◽  
Josie Rawes ◽  
Diana Worrall
Keyword(s):  
Radio Galaxy ◽  
Radio Galaxies ◽  
Jet Flows ◽  
Low Density ◽  
Intergalactic Gas ◽  
X Ray ◽  
Hot Gas ◽  
Gas Cavity ◽  
Gas Cloud ◽  
Ring Shaped Structure

AbstractJets often display bends and knots at which the flows change character. Extreme distortions have implications for the nature of jet flows and their interactions. We present the results of three radio mapping campaigns. The distortion of 3CRR radio galaxy NGC 7385 is caused by a collision with a foreground magnetised gas cloud which causes Faraday rotation and free-free absorption, and is triggered into star formation. For NGC 6109 the distortion is more extreme, creating a ring-shaped structure, but no deflector can be identified in cold or hot gas. Similar distortions in NGC 7016 are apparently associated with an X-ray gas cavity, and the adjacent NGC 7018 shows filaments drawn out beyond 100 kpc. Encounters with substructures in low-density, magnetised, intergalactic gas are likely causes of many of these features.

scholarly journals X-ray emission from the nuclei, lobes and hot-gas environments of two FR II radio galaxies

2004 ◽  
Vol 353 (3) ◽  
pp. 879-889 ◽  
Author(s):  
J. H. Croston ◽  
M. Birkinshaw ◽  
M. J. Hardcastle ◽  
D. M. Worrall
Keyword(s):  
Radio Galaxies ◽  
X Ray ◽  
Hot Gas

scholarly journals Radio and X-ray Observations of the Restarted Radio Galaxy in the Galaxy Cluster CL 0838+1948

Galaxies ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 108
Author(s):  
Simona Giacintucci ◽  
Tracy Clarke ◽  
Namir E. Kassim ◽  
Wendy Peters ◽  
Emil Polisensky
Keyword(s):  
Radio Source ◽  
Survey Data ◽  
Radio Galaxy ◽  
Galaxy Cluster ◽  
Gas Emission ◽  
Low Frequencies ◽  
Nuclear Activity ◽  
X Ray ◽  
Hot Gas ◽  
The Galaxy

We present VLA Low-band Ionosphere and Transient Experiment (VLITE) 338 MHz observations of the galaxy cluster CL 0838+1948. We combine the VLITE data with Giant Metrewave Radio Telescope 610 MHz observations and survey data. The central galaxy hosts a 250 kpc source whose emission is dominated by two large lobes at low frequencies. At higher frequencies, a pair of smaller lobes (∼30 kpc) is detected within the galaxy optical envelope. The observed morphology is consistent with a restarted radio galaxy. The outer lobes have a spectral index αout=1.6, indicating that they are old, whereas the inner lobes have αinn=0.6, typical for an active source. Spectral modeling confirms that the outer emission is a dying source whose nuclear activity switched off not more than 110 Myr ago. Using archival Chandra X-ray data, we compare the radio and hot gas emission. We find that the active radio source is contained within the innermost and X-ray brightest region, possibly a galactic corona. Alternatively, it could be the remnant of a larger cool core whose outer layers have been heated by the former epoch of activity that has generated the outer lobes.

scholarly journals Detecting shocked intergalactic gas with X-ray and radio observations

2019 ◽  
Vol 627 ◽  
pp. A5 ◽  
Author(s):  
F. Vazza ◽  
S. Ettori ◽  
M. Roncarelli ◽  
M. Angelinelli ◽  
M. Brüggen ◽  
...  
Keyword(s):  
Large Scale ◽  
Intergalactic Medium ◽  
Thermal Emission ◽  
Intergalactic Gas ◽  
Radio Observations ◽  
X Ray ◽  
Large Scale Structures ◽  
Hot Gas ◽  
Scale Structures ◽  
Radio Band

Detecting the thermal and non-thermal emission from the shocked cosmic gas surrounding large-scale structures represents a challenge for observations, as well as a unique window into the physics of the warm-hot intergalactic medium. In this work, we present synthetic radio and X-ray surveys of large cosmological simulations in order to assess the chances of jointly detecting the cosmic web in both frequency ranges. We then propose best observing strategies tailored for existing (LOFAR, MWA, and XMM) or future instruments (SKA-LOW and SKA-MID, Athena, and eROSITA). We find that the most promising targets are the extreme peripheries of galaxy clusters in an early merging stage, where the merger causes the fast compression of warm-hot gas onto the virial region. By taking advantage of a detection in the radio band, future deep X-ray observations will probe this gas in emission, and help us to study plasma conditions in the dynamic warm-hot intergalactic medium with unprecedented detail.

scholarly journals Deep XMM-Newton observations of the northern disc of M31

2020 ◽  
Vol 637 ◽  
pp. A12
Author(s):  
Patrick J. Kavanagh ◽  
Manami Sasaki ◽  
Dieter Breitschwerdt ◽  
Miguel A. de Avillez ◽  
Miroslav D. Filipović ◽  
...  
Keyword(s):  
Massive Stars ◽  
Low Density ◽  
Plasma Properties ◽  
X Ray ◽  
Star Forming ◽  
Hot Gas ◽  
Grand Design ◽  
Multi Wavelength ◽  
Multi Phase ◽  
Extended Emission

Aims. We use new deep XMM-Newton observations of the northern disc of M31 to trace the hot interstellar medium (ISM) in unprecedented detail and to characterise the physical properties of the X-ray emitting plasmas. Methods. We used all XMM-Newton data up to and including our new observations to produce the most detailed image yet of the hot ISM plasma in a grand design spiral galaxy such as our own. We compared the X-ray morphology to multi-wavelength studies in the literature to set it in the context of the multi-phase ISM. We performed spectral analyses on the extended emission using our new observations as they offer sufficient depth and count statistics to constrain the plasma properties. Data from the Panchromatic Hubble Andromeda Treasury were used to estimate the energy injected by massive stars and their supernovae. We compared these results to the hot gas properties. Results. The brightest emission regions were found to be correlated with populations of massive stars, notably in the 10 kpc star-forming ring. The plasma temperatures in the ring regions are ~0.2 up to ~0.6 keV. We suggest this emission is hot ISM heated in massive stellar clusters and superbubbles. We derived X-ray luminosities, densities, and pressures for the gas in each region. We also found large extended emission filling low density gaps in the dust morphology of the northern disc, notably between the 5 and 10 kpc star-forming rings. We propose that the hot gas was heated and expelled into the gaps by the populations of massive stars in the rings. Conclusions. It is clear that the massive stellar populations are responsible for heating the ISM to X-ray emitting temperatures, filling their surroundings, and possibly driving the hot gas into the low density regions. Overall, the morphology and spectra of the hot gas in the northern disc of M31 is similar to other galaxy discs.

Young radio sources at high-energies and the γ-ray CSO PKS 1718–649

2018 ◽  
Vol 14 (S342) ◽  
pp. 176-179
Author(s):  
Giulia Migliori
Keyword(s):  
Radio Galaxy ◽  
Radio Galaxies ◽  
High Energy ◽  
Radio Sources ◽  
Host Galaxies ◽  
X Ray ◽  
High Energies ◽  
Γ Rays ◽  
Γ Ray ◽  
High Energy Emission

AbstractObservations at high-energies are important to define the first stages of the evolution of extragalactic radio sources and to characterize the interstellar medium of their host galaxies. In some of the X-ray-observed Compact Symmetric Objects (CSOs, among the youngest and most compact radio galaxies), we measured values of the total hydrogen column densities large enough to slow or prevent the radio source growth. The γ-ray window has the potential to constrain the non-thermal contribution of jets and lobes to the total high-energy emission. However, so far, young radio sources remain elusive in γ-rays, with only a handful of detections (or candidates) reported by Fermi. I present our γ-ray study of the CSO PKS 1718–649, and draw comparison with the restarted, γ-ray detected, radio galaxy 3C 84.

scholarly journals The Evaporation of Nearby Clouds and the Soft X-ray Background

1997 ◽  
Vol 166 ◽  
pp. 169-172
Author(s):  
Jonathan D. Slavin
Keyword(s):  
Solar System ◽  
Thermal Conduction ◽  
Low Density ◽  
Local Bubble ◽  
X Ray ◽  
Hot Gas ◽  
Single Temperature ◽  
Temperature Equilibrium ◽  
X Ray Background ◽  
The One

AbstractIn recent years the nature of the low density clouds within the Local Bubble has been increasingly well characterized. These clouds, including the one which surrounds the solar system, are embedded in the hot gas and therefore should be evaporating via thermal conduction. If several evaporation fronts exist within the Local Bubble, the emissivity and spectrum of the hot gas is significantly different from a single temperature, equilibrium ionization plasma. We explore models in which the the temperature, density and ionization in the hot gas are influenced by cloud evaporation and compare the results with the observed Soft X-ray Background.

scholarly journals A rare case of FR I interaction with a hot X-ray bridge in the A2384 galaxy cluster

2019 ◽  
Author(s):  
V Parekh ◽  
T F Laganá ◽  
K Thorat ◽  
K van der Heyden ◽  
A Iqbal ◽  
...  
Keyword(s):  
Radio Galaxy ◽  
Galaxy Cluster ◽  
Plasma Properties ◽  
X Ray ◽  
Hot Gas ◽  
Radio Jets ◽  
Radio Lobe ◽  
Unique System ◽  
Varying Mass ◽  
Two Bodies

Abstract Clusters of varying mass ratios can merge and the process significantly disturbs the cluster environments and alters their global properties. Active radio galaxies are another phenomenon that can also affect cluster environments. Radio jets can interact with the intra-cluster medium (ICM) and locally affect its properties. Abell 2384 (hereafter A2384) is a unique system that has a dense, hot X-ray filament or bridge connecting the two unequal mass clusters A2384(N) and A2384(S). The analysis of its morphology suggests that A2384 is a post-merger system where A2384(S) has already interacted with the A2384(N), and as a result hot gas has been stripped over a ∼1 Mpc region between the two bodies. We have obtained its 325 MHz GMRT data, and we detected a peculiar FR I type radio galaxy which is a part of the A2384(S). One of its radio lobes interacts with the hot X-ray bridge and pushes the hot gas in the opposite direction. This results in displacement in the bridge close to A2384(S). Based on Chandra and XMM-Newton X-ray observations, we notice a temperature and entropy enhancement at the radio lobe-X-ray plasma interaction site, which further suggests that the radio lobe is changing thermal plasma properties. We have also studied the radio properties of the FR I radio galaxy, and found that the size and radio luminosity of the interacting north lobe of the FR I galaxy are lower than those of the accompanying south lobe.

X-Ray Astronomy

1969 ◽  
Vol 13 ◽  
pp. 289-312
Author(s):  
Herbert Friedman
Keyword(s):  
Radio Galaxy ◽  
Galactic Plane ◽  
Background Radiation ◽  
Galactic Latitude ◽  
Intergalactic Gas ◽  
High Galactic Latitude ◽  
X Ray ◽  
Diffuse Background ◽  
Distant Radio Galaxy ◽  
Radio Power

Although searches so far have been restricted to a few small rockets and balloons, some 40 discrete x-ray sources have already been resolved against a diffuse, nearly isotropic background radiation. The strongest source is about 2000 times as bright as the weakest detectable with present rocket instruments. Nearly all of the discrete sources lie close to the galactic plane and most likely are members of the spiral arms of the Milky Way. One x-ray source at high galactic latitude is identifiable with a distant radio galaxy, Virgo A, and its x-ray luminosity is 70 times its radio power. The diffuse background radiation seems to be resolvable into at least two components: one may be associated with the interaction of cosmic rays and the microwave photons of the cosmological 3 K background; the other with bremsstrahlung from hot, intergalactic gas.

Spectra of Radio Galaxies in Clusters

1982 ◽  
Vol 4 (4) ◽  
pp. 431-434 ◽  
Author(s):  
O. B. Slee ◽  
I. R. G. Wilson ◽  
Betty C. Siegman
Keyword(s):  
Electron Density ◽  
Radio Galaxy ◽  
Radio Galaxies ◽  
Relativistic Electrons ◽  
Number Of Clusters ◽  
X Ray ◽  
Thermal Spectrum ◽  
Cluster Centre ◽  
Intracluster Gas

There has been considerable speculation in recent years about the evolution of radio galaxies in clusters. The discovery of powerful X-ray emission with an apparently thermal spectrum from a considerable number of clusters has been attributed to a hot (108K) intracluster gas with an electron density of ∼ 10-3 cm -3 at the cluster centre (see e.g. McHardy 1978). Such a gas surrounding a radio galaxy may conceivably retard the expansion or diffusion of the relativistic electrons and thus allow the source to retain its identity for longer intervals than is the case for field galaxies.

scholarly journals X-ray analysis of the accreting supermassive black hole in the radio galaxy PKS 2251+11

2019 ◽  
Vol 625 ◽  
pp. A26
Author(s):  
S. Ronchini ◽  
F. Tombesi ◽  
F. Vagnetti ◽  
F. Panessa ◽  
G. Bruni
Keyword(s):  
Black Hole ◽  
Power Law ◽  
Radio Galaxy ◽  
Timing Analysis ◽  
Seyfert Galaxies ◽  
Radio Galaxies ◽  
Broad Line ◽  
X Ray ◽  
Supermassive Black Hole ◽  
Link Type

Context. We have investigated the dichotomy between jetted and non-jetted active galactic nuclei (AGNs), focusing on the fundamental differences of these two classes in the accretion physics onto the central supermassive black hole (SMBH). We tested the validity of the unification model of AGNs through the characterization of the mutual interaction between accreting and outflowing matter in radio galaxies. Aims. Our aim is to study and constrain the structure, kinematics and physical state of the nuclear environment in the broad line radio galaxy (BLRG) PKS 2251+11. The high X-ray luminosity and the relative proximity make such AGN an ideal candidate for a detailed analysis of the accretion regions in radio galaxies. The investigation will help to shed light on the analogies and differences between the BLRGs and the larger class of radio-quiet Seyfert galaxies and hence on the processes that trigger the launch of a relativistic jet. Methods. We performed a spectral and timing analysis of a ∼64 ks observation of PKS 2251+11 in the X-ray band with XMM-Newton. We modeled the spectrum considering an absorbed power law superimposed to a reflection component. We performed a time-resolved spectral analysis to search for variability of the X-ray flux and of the individual spectral components. Results. We find that the power law has a photon index Γ = 1.8 ± 0.1, absorbed by an ionized partial covering medium with a column density NH = (10.1 ± 0.8) × 1023 cm−2, a ionization parameter log ξ = 1.3 ± 0.1 erg s−1 cm and a covering factor f ≃ 90%. Considering a density of the absorber typical of the broad line region (BLR), its distance from the central SMBH is of the order of r ∼ 0.1 pc. An Fe Kα emission line is found at 6.4 keV, whose intensity shows variability on timescales of hours. We derive that the reflecting material is located at a distance r ≳ 600rs, where rs is the Schwarzschild radius. Conclusions. Concerning the X-ray properties, we found that PKS 2251+11 does not differ significantly from the non-jetted AGNs, confirming the validity of the unified model in describing the inner regions around the central SMBH, but the lack of information regarding the state of the very innermost disk and SMBH spin still leaves unconstrained the origin of the jet.

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