scholarly journals X-ray emission from the extended emission-line region of the powerful radio galaxy 3C 171

2010 ◽  
Vol 401 (4) ◽  
pp. 2697-2705 ◽  
Author(s):  
M. J. Hardcastle ◽  
F. Massaro ◽  
D. E. Harris
Keyword(s):  
Emission Line ◽  
Radio Galaxy ◽  
Powerful Radio ◽  
X Ray ◽  
Line Region ◽  
Extended Emission ◽  
Powerful Radio Galaxy

scholarly journals The ASCA X-ray spectrum of the powerful radio galaxy 3C 109

1997 ◽  
Vol 286 (3) ◽  
pp. 765-770 ◽  
Author(s):  
S. W. Allen ◽  
A. C. Fabian ◽  
E. Idesawa ◽  
H. Inoue ◽  
T. Kii ◽  
...  
Keyword(s):  
Radio Galaxy ◽  
Powerful Radio ◽  
X Ray ◽  
Powerful Radio Galaxy

scholarly journals Probing the pc- and kpc-scale Environment of the Powerful Radio Galaxy Hercules A

2002 ◽  
Vol 19 (1) ◽  
pp. 69-72 ◽  
Author(s):  
Nectaria A. B. Gizani ◽  
M. A. Garrett ◽  
J. P. Leahy
Keyword(s):  
Radio Source ◽  
Radio Galaxy ◽  
Angular Size ◽  
Position Angle ◽  
Extragalactic Radio Source ◽  
X Ray ◽  
Central Value ◽  
Intracluster Gas ◽  
Extended Emission ◽  
Powerful Radio Galaxy

AbstractWe present the kpc-scale behaviour of the powerful extragalactic radio source Hercules A and the behaviour of the intracluster gas in which the radio source is situated. We have found that Hercules A exhibits a strong Laing-Garrington effect. The X-ray observations have revealed an extended X-ray emission elongated along the radio galaxy axis. The estimated temperature of the cluster is kT=2.45 keV and the central electron density is n○≃7.8×10−3 cm−3 which reveals a hot, dense environment in which Hercules A is situated. From the combined study of the radio and X-ray data we have estimated a central value of 3 ≲ B○(μG)≲9.We also present the most recent results from the analysis of the radio data on the pc-scale structure of the radio galaxy, observed at 18 cm by the EVN–MERLIN array. A faint but compact radio source, coincident with the optical centre of Hercules A, was detected by the EVN at 18 mas resolution. The total flux density of the EVN core is 14.6 mJy. Its angular size is 18×7 mas with a position angle of ≃139°. There is also evidence for extended emission in the NW–SE direction, most probably from the eastern pc-scale jet. If this is true then there is a misalignment between the direction of the pc-eastern and the aligned kpc-scale jets of ≃35°.

scholarly journals Extended and Compact X‐Ray Emission from the Powerful Radio Galaxy 3C 220.1

1998 ◽  
Vol 504 (2) ◽  
pp. 743-748 ◽  
Author(s):  
M. J. Hardcastle ◽  
C. R. Lawrence ◽  
D. M. Worrall
Keyword(s):  
Radio Galaxy ◽  
Powerful Radio ◽  
X Ray ◽  
Powerful Radio Galaxy

scholarly journals Cygnus A ? John Bolton?s First Cosmic Source

1994 ◽  
Vol 47 (5) ◽  
pp. 615 ◽  
Author(s):  
DE Harris
Keyword(s):  
Radio Galaxy ◽  
Discrete Source ◽  
X Rays ◽  
Powerful Radio ◽  
X Ray ◽  
Cygnus A ◽  
Cosmic Source ◽  
Powerful Radio Galaxy

Using a sea interferometer, Bolton and Stanley isolated Cygnus A as a discrete source in 1948. It is a prime example� of a powerful radio galaxy and, in the last decade, has also been studied extensively in X-rays. In this paper I summarise the results from a ROSAT X-ray image.

scholarly journals A Powerful Jet/Cloud Interaction in the Radio Galaxy PKS 2250-41

1996 ◽  
Vol 175 ◽  
pp. 227-229
Author(s):  
R. Morganti ◽  
C.N. Tadhunter ◽  
N. Clark ◽  
N. Killeen
Keyword(s):  
Emission Line ◽  
Strong Evidence ◽  
Radio Galaxy ◽  
High Redshift ◽  
Radio Galaxies ◽  
Radio Sources ◽  
Excitation Mechanism ◽  
Powerful Radio ◽  
Radio Jets ◽  
Extended Emission

Extended emission line regions aligned with the radio axis are a common feature of powerful radio galaxies and there is much interest in the origin of the extended gas and excitation mechanism. One model that can produce this alignment is photoionization by anisotropic nuclear continuum radiation. However, strong evidence exists, especially in high redshift radio galaxies, for powerful interactions between the relativistic radio jets and the ISM/IGM. Here we present the results of our study of the southern radio galaxy PKS 2250–41 (z = 0.308). This object is the most spectacular found in a sample of southern radio sources studied by Tadhunter et al. (1993) and it displays particularly clear evidence for such an interaction (Tadhunter et al. 1994; Dickson et al. 1995).

scholarly journals X-ray and lensing results on the cluster around the powerful radio galaxy 4C+55.16

1999 ◽  
Vol 306 (2) ◽  
pp. 467-472 ◽  
Author(s):  
K. Iwasawa ◽  
S. W. Allen ◽  
A. C. Fabian ◽  
A. C. Edge ◽  
S. Ettori
Keyword(s):  
Radio Galaxy ◽  
Powerful Radio ◽  
X Ray ◽  
Powerful Radio Galaxy

scholarly journals A young and obscured AGN embedded in the giant radio galaxy Mrk 1498

2019 ◽  
Author(s):  
L Hernández-García ◽  
F Panessa ◽  
L Bassani ◽  
G Bruni ◽  
F Ursini ◽  
...  
Keyword(s):  
Large Scale ◽  
Radio Galaxy ◽  
Conclusive Evidence ◽  
X Rays ◽  
Nuclear Activity ◽  
X Ray ◽  
Multi Wavelength ◽  
Tidal Streams ◽  
A Minor ◽  
Extended Emission

Abstract Mrk 1498 is part of a sample of galaxies with extended emission line regions (extended outwards up to a distance of ∼7 kpc) suggested to be photo-ionized by an AGN that has faded away or that is still active but heavily absorbed. Interestingly, the nucleus of Mrk 1498 is at the center of two giant radio lobes with a projected linear size of 1.1 Mpc. Our multi-wavelength analysis reveals a complex nuclear structure, with a young radio source (Giga-hertz Peaked Spectrum) surrounded by a strong X-ray nuclear absorption, a mid-infrared spectrum that is dominated by the torus emission, plus a circum-nuclear extended emission in the [OIII] image (with radius of ∼ 1 kpc), most likely related to the ionization of the AGN, aligned with the small and large scale radio jet and extended also at X-rays. In addition a large-scale extended emission (up to ∼ 10 kpc) is only visible in [OIII]. These data show conclusive evidence of a heavily absorbed nucleus and has recently restarted its nuclear activity. To explain its complexity, we propose that Mrk 1498 is the result of a merging event or secular processes, such as a minor interaction, that has triggered the nuclear activity and produced tidal streams. The large-scale extended emission that gives place to the actual morphology could either be explained by star formation or outflowing material from the AGN.

scholarly journals The X-Ray Nova GRO J0422+32 in Decline and Quiescence

1996 ◽  
Vol 158 ◽  
pp. 399-400
Author(s):  
M. R. Garcia ◽  
P. J. Callanan ◽  
J. E. McClintock ◽  
P. Zhao
Keyword(s):  
Emission Line ◽  
Emission Region ◽  
Dwarf Novae ◽  
X Ray ◽  
First Order ◽  
Band Emission ◽  
Line Region ◽  
Hα Emission ◽  
The Stability ◽  
The Continuum

We have followed the X-ray nova GRO J0422+32, spectroscopically and photometrically, throughout the decline to quiescence.In the final stages of decay (days 430…880 after the outburst, see Callanan et al. (1995) for the epoch 1995), the equivalent width (EW) of the Hα emission increases monotonically and the R magnitude decreases monotonically. This suggests that the flux in the Hα line is constant, while the continuum fades. The Hα flux is the product of the R band flux (F(R), arbitrarily scaled to 100 at R = 19 mag) and the EW, and is shown in the last column of the table below. The Hα flux varies by only ~ 30% while the continuum fades by a factor of eight (from R = 19 mag to R = 21.3 mag). So, to first order, the Hα luminosity is constant in the final stages of decay. While it is generally the case that the emission line EWs in individual dwarf novae also increase during the decay, the exact behavior seen in GRO J0422+32 is not what is seen for dwarf novae (on average). Using the relation between EW[Hβ] and Mv given in figure 6 of Patterson (1984), we would expect a factor of ~ 5 variation in the Hα flux during days 430…880. The stability of the Hα flux implies that somehow the emission line region is ‘disconnected’ from the continuum (R–band) emission region.

Sign in / Sign up

Export Citation Format

Share Document