2002/02/17 by A. S. Wilson, Wilson, A. S., K. A. Arnaud +7
Physics and Astronomy · #Astrophysics (astro-ph) #FOS: Physical sciences #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0202319
9 pages, 12 figures, to be published in ``New Visions of the Universe in the XMM-Newton and Chandra Era'', Ed. F. Jansen (in press) (2002) (European Space Agency ESA SP-488)
arxiv created 2002/02/17 · arxiv updated 2009/12/01
We report Chandra imaging-spectroscopy and RXTE spectroscopy of the nearby, powerful radio galaxy Cygnus A. Various aspects of the results are discussed, including the X-ray properties of the nucleus, the radio hot spots, the cluster of galaxies, the prolate cavity in the ICM inflated by the radio jets and ``bands'' of thermal gas which encircle the cavity in its equatorial plane. The hard X-ray emission of the nucleus extends to 100 keV and originates from an unresolved source absorbed by a large column density (N\rm H ≃ 2 × 1023 cm-2) of gas. The soft (< 2 keV) nuclear emission exhibits a bi-polar structure which extends ≃ 2 kpc from the nucleus and is strongly correlated with both optical continuum and emission-line morphologies. It is suggested that this nebulosity is photoionized by the nucleus and that the extended X-rays are electron-scattered nuclear radiation. All four radio hot spots are detected in X-rays, with the emission resulting from synchrotron self-Compton radiation in an approximately equipartition field. The temperature of the X-ray emitting intracluster gas drops from ≃ 8 keV more than 100 kpc from the center to ≃ 5 keV some 80 kpc from the center, with the coolest gas immediately adjacent to the radio galaxy. There is a metallicity gradient in the X-ray emitting gas, with the highest metallicities (∼ solar) found close to the center, decreasing to ∼ 0.3 solar in the outer parts. (Abstract truncated).