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arXiv · 1004.0191

A Flare in the Jet of Pictor A

H. L. Marshall·M. J. Hardcastle·M. Birkinshaw·J. Croston·D. Evans·H. Landt·E. Lenc·F. Massaro·E. S. Perlman·D. A. Schwartz·A. Siemiginowska·Ł. Stawarz·C. M. Urry·D. M. Worrall
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Abstract

A Chandra X-ray imaging observation of the jet in Pictor A showed a feature that appears to be a flare that faded between 2000 and 2002. The feature was not detected in a follow-up observation in 2009. The jet itself is over 150 kpc long and a kpc wide, so finding year-long variability is surprising. Assuming a synchrotron origin of the observed high-energy photons and a minimum energy condition for the outflow, the synchrotron loss time of the X-ray emitting electrons is of order 1200 yr, which is much longer than the observed variability timescale. This leads to the possibility that the variable X-ray emission arises from a very small sub-volume of the jet, characterized by magnetic field that is substantially larger than the average over the jet.

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H. L. Marshall, M. J. Hardcastle, M. Birkinshaw, J. Croston, D. Evans, H. Landt, E. Lenc, F. Massaro, E. S. Perlman, D. A. Schwartz, A. Siemiginowska, Ł. Stawarz, C. M. Urry, D. M. Worrall. 2010-04-01. A Flare in the Jet of Pictor A. https://doi.org/10.1088/2041-8205%2F714%2F2%2Fl213

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