Theory
Interpretation of Blazar Data
Our theoretical work focuses on the interpretation of
multiwavelength observations of gamma-ray blazars.
We model the non-thermal continuum emission from these
objects with so-called synchrotron Self-Compton models (see figure on the left hand side).
The modeling work allows us to assess the physical parameters
describing the bulk motion of the jet plasma as well as to
"measure" the magnetic field inside the jets.
A very exciting by-product of modeling X-ray/TeV gamma-ray
data from TeV gamma-ray loud blazars is the possibility
to predict the TeV gamma-ray energy spectrum from the observed
X-ray energy spectrum. Comparison of the predicted and
observed energy spectra allows us to estimate the extent
of extragalactic TeV gamma-ray absorption in
pair-production processes of TeV photons interacting with
infrared photons.
The method enables us to "measure" the intensity of the
infrared background radiation. The latter constrains the
total electromagnetic energy production of the universe and
thus the very early history of galaxy and star formation at
redshifts of z=10.
Link to the Whipple/VERITAS Multiwavelength Group Page
X-Ray Emission from Jets of Radio Galaxies
The Chandra X-ray observatory discovered X-ray emission from a large number of kpc scale AGN jets. We are exploring possibilities to explain the X-ray emission either as synchrotron emission from several distinct populations of relativistic electrons, or as Inverse Compton emission from electrons scattering off the Cosmic Microwave Background, assuming that the jet plasma moves highly relativistically towards the observer. Work is ongoing to decide between these two explanations.