High resolution X-ray observation and monitoring of the x-ray jet and radio lobes of Centaurus A

Abstract

We summarize the results of our Chandra AO-1 observations of the X-ray jet in the nearby radio galaxy Centaurus A, and discuss preliminary results from our ongoing monitoring campaign, the first observation of which was made in September, 2002. Our AO-1 observations demonstrate that there are small but significant differences in the X-ray and radio morphologies of the jet in this prototypical FR I radio galaxy. We conclude that the X-ray emission was due to synchrotron radiation from a population of ultra-relativistic electrons, and that the morphological differences can be explained by physical separation of the radio and X-ray emitting electron populations through aging and diffusion. This synchrotron hypothesis can be tested because the lifetime of the X-ray emitting electrons is only a few tens of years. Statistically significant spectral and intensity variations in the knots of the jet should be detectable with Chandra on the timescales of years. As part of our monitoring campaign, we are searching for super-luminal motion in the knots of the jet to evaluate the importance of bulk relativistic motion. Finally, we also discuss the nature of the X-ray enhancement in the vicinity of the outer half of the inner SW radio lobe.