The infrared jet in Centaurus A: multiwavelength constraints on emission mechanisms and particle acceleration

Abstract

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, 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.

Accepted by MN letters. 5 pages, 4 colour figures. Some figures reduced in quality. v2 fixes two typos, no other changes

References in corpus (1)

• Chandra and XMM-Newton Observations of the Nucleus of Centaurus A

Cited by in corpus (9)

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• Gemini Imaging of Mid-IR Emission from the Nuclear Region of Centaurus A
• LABOCA observations of nearby, active galaxies
• A Chandra Study of the Lobe/ISM Interactions Around the Inner Radio Lobes of Centaurus A: Constraints on the Temperature Structure and Transport Processes
• A Two Zone Synchrotron Model for the Knots in the M87 Jet
• Knot in Cen A: Stochastic Magnetic Field for Diffusive Synchrotron Radiation?