Time-dependent Inhomogeneous Jet Models for BL Lac Objects
Marlowe, A.(JHU), Urry, C.M.(STScI), George,I.M. (NASA)
Abstract
Relativistic beaming can explain many of the observed properties of BL Lac
objects (e.g., rapid variability, high polarization, etc.). In particular, the
broadband radio through X-ray spectra are well modeled by synchrotron-self
Compton emission from an inhomogeneous relativistic jet. We have done a
uniform analysis on several BL Lac objects using a simple but plausible
inhomogeneous jet model. For all objects, we found that the assumed
power-law distribution of the magnetic field and the electron density can be
adjusted to match the observed BL Lac spectrum. While such models are
typically unconstrained, consideration of spectral variability strongly restricts
the allowed parameters, although to date the sampling has generally been too
sparse to constrain the current models effectively. We investigate the time
evolution of the inhomogeneous jet model for a simple perturbation
propagating along the jet. The implications of this time evolution model and its
relevance to observed data are discussed.
NASA/STI Keywords: ASTRONOMICAL MODELS, BL LACERTAE OBJECTS, RADIO JETS
(ASTRONOMY), RADIO SPECTRA, RELATIVISTIC THEORY, X
RAY SPECTRA, BROADBAND, COMPTON EFFECT,
INHOMOGENEITY, TIME DEPENDENCE