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 _ { H } \simeq 2 \times 10 ^ { 23 } cm ^ { -2 } ) of gas .
The soft ( < 2 keV ) nuclear emission exhibits a bi-polar structure which extends \simeq 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 \simeq 8 keV more than 100 kpc from the center to \simeq 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 ( \sim solar ) found close to the center , decreasing to \sim 0.3 solar in the outer parts .
We have used the assumption of hydrostatic equilibrium to derive a total cluster mass within 500 kpc of 2.0 \times 10 ^ { 14 } M _ { \odot } and 2.8 \times 10 ^ { 14 } M _ { \odot } , and a gas fraction in the cluster within 500 kpc of 0.055 and 0.039 for a constant and centrally decreasing temperature profile , respectively .
We show that the limb-brightened edge of the cavity is hotter than the nearby , innermost region of the cluster gas , indicating heating by the expanding , jet-driven cavity .
Conversely , the “ bands ” , interpreted as gas being accreted onto the galaxy , are cooler .
Within the cavity , there is evidence for diffuse X-ray emission , in addition to the X-ray emissions related to the jets and hot spots .