A Flare in the Jet of Pictor A
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.
Cite
@article{arxiv.1004.0191,
title = {A Flare in the Jet of Pictor A},
author = {H. L. Marshall and M. J. Hardcastle and M. Birkinshaw and J. Croston and D. Evans and H. Landt and E. Lenc and F. Massaro and E. S. Perlman and D. A. Schwartz and A. Siemiginowska and Ł. Stawarz and C. M. Urry and D. M. Worrall},
journal= {arXiv preprint arXiv:1004.0191},
year = {2015}
}
Comments
12 pages, 3 figures, to appear in Ap. J. Letters