A multi-zone model for simulating the high energy variability of TeV blazars

TL;DR

This paper introduces a time-dependent multi-zone simulation code for TeV blazars that models variability by considering non-local SSC losses and light travel time delays, improving upon simpler one-zone models.

Contribution

The novel multi-zone code incorporates non-local SSC losses and light travel time effects, providing a more realistic simulation of blazar variability with minimal additional parameters.

Findings

Successfully models TeV blazar variability with non-local SSC effects.

Efficient computational implementation using simplified SSC expressions.

Provides a tool for interpreting multi-wavelength observations of blazars.

Abstract

We present a time-dependent multi-zone code for simulating the variability of Synchrotron-Self Compton (SSC) sources. The code adopts a multi-zone pipe geometry for the emission region, appropriate for simulating emission from a standing or propagating shock in a collimated jet. Variations in the injection of relativistic electrons in the inlet propagate along the length of the pipe cooling radiatively. Our code for the first time takes into account the non-local, time-retarded nature of synchrotron self-Compton (SSC) losses that are thought to be dominant in TeV blazars. The observed synchrotron and SSC emission is followed self-consistently taking into account light travel time delays. At any given time, the emitting portion of the pipe depends on the frequency and the nature of the variation followed. Our simulation employs only one additional physical parameter relative to one-zone models, that of the pipe length and is computationally very efficient, using simplified expressions for the SSC processes. The code will be useful for observers modeling GLAST, TeV, and X-ray observations of SSC blazars.