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The Knotty Question of the Jet of PKS B1421-490

J. M. Gelbord·H. L. Marshall·D. M. Worrall·M. Birkinshaw·J. E. J. Lovell·R. Ojha·L. Godfrey·D. A. Schwartz·E. S. Perlman·M. Georganopoulos·D. W. Murphy·D. L. Jauncey
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Abstract

We report the discovery of unusually strong optical and X-ray emission associated with a knot in the radio jet of PKS B1421-490. The knot is the brightest feature observed beyond the radio band, with knot/core flux ratios \~300 and 3.7 at optical and X-ray frequencies. We interpret the extreme optical output of the knot as synchrotron emission. The nature of the X-ray emission is unclear. We consider a second synchrotron component, inverse Compton emission from a relativistic, decelerating jet, and the possibility that this feature is a chance superposition of an unusual BL Lac object.

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J. M. Gelbord, H. L. Marshall, D. M. Worrall, M. Birkinshaw, J. E. J. Lovell, R. Ojha, L. Godfrey, D. A. Schwartz, E. S. Perlman, M. Georganopoulos, D. W. Murphy, D. L. Jauncey. 2005-09-08. The Knotty Question of the Jet of PKS B1421-490. https://doi.org/10.1086/497823

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