Radio Lobes of Pictor A: an X-ray spatially resolved Study

Abstract

A new XMM observation has made possible a detailed study of both lobes of the radio galaxy Pictor A. Their X-ray emission is of non thermal origin and due to Inverse Compton scattering of the microwave background photons by relativistic electrons in the lobes, as previously found. In both lobes, the equipartition magnetic field (Beq) is bigger than the Inverse Compton value (Bic), calculated from the radio and X-ray flux ratio. The Beq/Bic ratio never gets below 2, in spite of the large number of reasonable assumptions tested to calculate Beq, suggesting a lobe energetic dominated by particles. The X-ray data quality is good enough to allow a spatially resolved analysis. Our study shows that Bic varies through the lobes. It appears to increase behind the hot spots. On the contrary, a rather uniform distribution of the particles is observed. As a consequence, the radio flux density variation along the lobes appears to be mainly driven by magnetic field changes.

15 pages, 3 figures, ApJ accepted

References in corpus (1)

• Discovery of the low-energy cutoff in a powerful giant radio galaxy

Cited by in corpus (16)

• Synchrotron and inverse-Compton emission from blazar jets I: a uniform conical jet model
• Radio spectral properties and jet duty cycle in the restarted radio galaxy 3C388
• Constraining the AGN duty cycle in the cool-core cluster MS 0735.6+7421 with LOFAR data
• Cosmic Magnetism in Centimeter and Meter Wavelength Radio Astronomy
• NuSTAR hard X-ray spectra of radio galaxies
• Origin of the X-rays and Possible GeV-TeV Emission from the Western Hot Spot Of Pictor A
• Stochastic Acceleration in the Western Hotspot of Pictor A
• Low-frequency observations of the Giant Radio Galaxy NGC 6251
• Multifrequency analysis of the radio emission from a post-merger galaxy CGCG 292-057
• Non-thermal emission in lobes of radio galaxies: III. 3C 98, Pictor A, DA 240, Cygnus A, 3C 326, and 3C 236
• AGN feedback in an infant galaxy cluster: the LOFAR-Chandra view of the giant FRII radio galaxy J103025+052430 at z=1.7
• X-ray Spectral Analysis of the Jet Termination Shock in Pictor A on Sub-Arcsecond Scales with Chandra
• Multiwavelength study of radio galaxy Pictor A: detection of western hotspot in far-UV and possible origin of high energy emissions
• Complex Structure of the Eastern Lobe of the Pictor A Radio Galaxy: Spectral Analysis and X-ray/Radio Correlations
• Probing AGN duty cycle and cluster-driven morphology in a giant episodic radio galaxy
• NuSTAR discovery of the hard X-ray emission and a wide-band X-ray spectrum from the Pictor A western hot spot