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arXiv · 0712.3579

Where Centaurus A gets its X-ray knottiness

Abstract

We report an X-ray spectral study of the transverse structure of the Centaurus A jet using new data from the Chandra Cen A Very Large Project. We find that the spectrum steepens with increasing distance from the jet axis, and that this steepening can be attributed to a change in the average spectrum of the knotty emission. Such a trend is unexpected if the knots are predominantly a surface feature residing in a shear layer between faster and slower flows. We suggest that the spectral steepening of the knot emission as a function of distance from the jet axis is due to knot migration, implying a component of transverse motion of knots within the flow.

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D. M. Worrall, M. Birkinshaw, R. P. Kraft, G. R. Sivakoff, A. Jordan, M. J. Hardcastle, N. J. Brassington, J. H. Croston, D. A. Evans, W. R. Forman, W. E. Harris, C. Jones, A. M. Juett, S. S. Murray, P. E. J. Nulsen, S. Raychaudhury, C. L. Sarazin, K. A. Woodley. 2007-12-20. Where Centaurus A gets its X-ray knottiness. https://doi.org/10.1086/528681

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