AChandraStudy of the Multicomponent X‐Ray Emission from the X‐shaped Radio Galaxy 3C 403

Abstract

We present results from a 49.4 ks Chandra/ACIS-S observation of the nearby (z=0.059) X-shaped FRII radio galaxy 3C 403. This is the first Chandra observation of an X-shaped radio galaxy, and one of the goals of this pioneering study is to determine the relationship between the X-ray emitting gas and the X-shaped radio morphology. We find that the X-ray isophotes of the hot gas within ∼3.5 ′′ of the central galaxy are highly elliptical (eccentricity∼0.57) and co-aligned with the elliptical optical isophotes. This supports the hypothesis that X-shaped radio sources are created by propagation of jets through asymmetric density distributions. Within large uncertainties, there is no evidence that the lobes or wings are overpressurized relative to the ISM, supporting the scenario in which the wings are the result of strong backflow of material from the jet head and subsequent buoyant evolution. We have detected X-ray emission from several of the radio knots to the E of the active nucleus, and diffuse emission from the radio lobe to the W. The X-ray emission from the eastern knots cannot be explained by an inverse Compton model unless they are far from equipartition. Using archival HST data, optical emission is detected from two knots, and the radio/optical/Xray spectra are well fitted by simple synchrotron models. This is one of the

ChandraandXMM‐NewtonObservations of a Sample of Low‐Redshift FR I and FR II Radio Galaxy Nuclei

“…The addition of a thermal Apec component did not significantly improve the fit ( 2 ¼ 29:0 for 48 dof, with the probability of achieving a greater F by chance of 18.4%). We compared the results of the spectral fitting to previously published Chandra data ( Kraft et al 2005) and found all parameter values to be consistent.…”

“…In total, 16 Chandra and 5 XMM-Newton observations of the sources are available at the time of writing, with the majority taken from the public data archives, together with some proprietary GO and GTO data. We compare results with those for Centaurus A ), 3C 403 (Kraft et al 2005), and 3C 405 (Cygnus A). Centaurus A is the nearest and best studied AGN, while 3C 403 and 3C 405 are nearby FR II-type sources, and so each provides a useful comparison with the other sources in our sample.…”

NewChandraObservations of the Jet in 3C 273. I. Softer X‐Ray than Radio Spectra and the X‐Ray Emission Mechanism

“…It would then be an obvious assumption that high-power jets are also able to accelerate such electrons. Indeed, some high-power jets show evidence for synchrotron X-ray emission (Sambruna et al 2004;Kraft et al 2005;Hardcastle & Croston 2005). Moreover, Stawarz & Ostrowski (2002), Rieger & Mannheim (2002), and Rieger & Duffy (2004) have all argued that efficient particle acceleration is possible in regions of velocity shear.…”

“…Since the increase of the CMB energy density with redshift would cancel the surface brightness dimming with redshift, beamed IC-CMB X-ray jets at high redshift could be cosmic beacons that outshine their quasars (Schwartz 2002). Moreover, there are jets in FR II radio galaxies and quasars whose X-ray emission is either well explained as synchrotron emission on an extrapolation of the radio-optical spectrum (e.g., in some of the jets in the survey by Sambruna et al [2004], and in 3C 403 [ Kraft et al 2005]) or because the necessary Doppler factors cannot be achieved from geometrical considerations, such as in Pictor A (Hardcastle & Croston 2005), in which there is X-ray emission from the counterjet as well as the approaching jet. A detailed check of the beamed IC-CMB model is therefore warranted.…”

Chandra Reveals Twin X-ray Jets in the Powerful FR II Radio Galaxy 3C 353

“…Such emission has, however, been detected in several objects (e.g., 3C 303, 3C 15, Pictor A, or 3C 403; see Kataoka et al 2003a,b, Hardcastle & Croston 2005, and Kraft et al 2005. Obviously, detection of any X-ray counterjet would be of primary importance in this respect, since it would automatically exclude significant beaming, and thus impose very severe constraints on the jet emission models.…”