ChandraObservations of the X‐Ray Jet in Centaurus A

We present high angular resolution X-ray images and spectra from two {\emChandra} ACIS-I observations of the X-ray jet in the nearby radio galaxyCentaurus A. We find that the X-ray emission from the jet is composed of a lowsurface brightness diffuse component extending continuously from within atleast 60 pc of the active nucleus into the NE radio lobe 4 kpc from thenucleus, along with 31 discrete compact knots, most of which are extended atthe resolution of our observation. We find that there are small but significantdifferences between the X-ray and radio morphologies of the inner jet at thearcsecond level, making it unlikely that a single, spatially coincidentpopulation of ultrarelativistic electrons is responsible for the emission inboth energy regimes. We suggest that the X-ray knots of the inner jet areindeed the sites of particle acceleration and shocks, and the X-ray and radioknot offsets are caused by a combination of particle diffusion and energy loss.These offsets may be a common feature of all jets in radio galaxies, or atleast jets in FR I type galaxies, and may be fundamental to the physics of suchjets. The X-ray spectra of several regions of the jet are well fit by absorbedpower-law models with photon indices $\sim$2.2-2.5, although the spectrum ofone bright knot located $\sim$1 kpc from the nucleus (knot B) is harder (photonindex = 2.0).Comment: 40 pages, 15 figures, 5 tables - Accepted for publication in the Astrophysical Journa