350 research outputs found
High Energy Variability Of Synchrotron-Self Compton Emitting Sources: Why One Zone Models Do Not Work And How We Can Fix It
With the anticipated launch of GLAST, the existing X-ray telescopes, and the
enhanced capabilities of the new generation of TeV telescopes, developing tools
for modeling the variability of high energy sources such as blazars is becoming
a high priority. We point out the serious, innate problems one zone
synchrotron-self Compton models have in simulating high energy variability. We
then present the first steps toward a multi zone model where non-local, time
delayed Synchrotron-self Compton electron energy losses are taken into account.
By introducing only one additional parameter, the length of the system, our
code can simulate variability properly at Compton dominated stages, a situation
typical of flaring systems. As a first application, we were able to reproduce
variability similar to that observed in the case of the puzzling `orphan' TeV
flares that are not accompanied by a corresponding X-ray flare.Comment: to appear in the 1st GLAST symposium proceeding
The JetCurry Code. I. Reconstructing Three-Dimensional Jet Geometry from Two-Dimensional images
We present a reconstruction of jet geometry models using numerical methods
based on a Markov ChainMonte Carlo (MCMC) and limited memory
Broyden-Fletcher-Goldfarb-Shanno (BFGS) optimized algorithm. Our aim is to
model the three-dimensional geometry of an AGN jet using observations, which
are inherently two-dimensional. Many AGN jets display complex hotspots and
bends over the kiloparsec scales. The structure of these bends in the jets
frame may be quite different than what we see in the sky frame, transformed by
our particular viewing geometry. The knowledge of the intrinsic structure will
be helpful in understanding the appearance of the magnetic field and hence
emission and particle acceleration processes over the length of the jet. We
present the method used, as well as a case study based on a region of the M87
jet.Comment: Submitted to ApJ on Feb 01, 201
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