Open AccessThe infrared jet in Centaurus A: multiwavelength constraints on emission mechanisms and particle acceleration
Author(s) -
Hardcastle M. J.,
Kraft R. P.,
Worrall D. M.
Publication year - 2006
Publication title -
monthly notices of the royal astronomical society: letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.067
H-Index - 122
eISSN - 1745-3933
pISSN - 1745-3925
DOI - 10.1111/j.1745-3933.2006.00146.x
Subject(s) - physics , astrophysics , centaurus a , flare , infrared , jet (fluid) , particle acceleration , astronomy , synchrotron , flux (metallurgy) , active galactic nucleus , acceleration , galaxy , optics , materials science , classical mechanics , metallurgy , thermodynamics
We report on Spitzer and Gemini observations of the jet of Centaurus A in the infrared, which we combine with radio, ultraviolet and X‐ray data. Spitzer detects jet emission from about 2 arcmin from the nucleus, the emission becoming particularly bright after the jet flare point at ∼3.4 arcmin. Where X‐ray and infrared emission are seen together the broad‐band data strongly support a synchrotron origin for the X‐rays. The jet flare point is marked by a broad, diffuse region of X‐rays which may be associated with a shock: we discuss possible physical mechanisms for this. The infrared jet persists after the flare point region although X‐ray emission is absent; it is plausible that here we are seeing the effects of particle acceleration followed by downstream advection with synchrotron losses. Gemini data probe the inner regions of the jet, putting limits on the mid‐infrared flux of jet knots.