event
Wednesday 16 Jan 2013: Jets on different scales: From Blazars to X-ray binaries
Dr Omar Jamil - Honorary Research Fellow of the University of Exeter (Met Office)
Physics, 4th floor 14:00-15:00
Although ubiquitous in nature, relativistic jets are still not fully understood. In the following talk I will discuss jets on very different scales. On the one end of this scale we have blazars which are one of the most energetic phenomena in the Universe and on the other end we have jets from stellar mass black holes. I will present first results from time-dependent blazar jet radiation transfer simulations. It evaluates self-consistently, and with full angular dependence, the synchrotron and synchrotron self-Compton emission which is particularly relevant for high-frequency-peaked BL Lac objects. I will show how the magnetic field orientation can play an important role in spectral energy distribution (SED) fits for blazars.
Another question that remains unanswered is the particle acceleration mechanism inside these jets. The flat radio to infra-red spectrum (due to self-absorbed synchrotron emission), observed frequently in X-ray binary sources, is considered to be a signature for the presence of a jet. However, most models that aim to explain such flat spectra are unable to reconcile the particle (adiabatic) energy losses. I shall present an internal shocks model for X-ray binary jets and show how it can be used to replenish the adiabatic energy losses and recover the flat spectrum. I shall also briefly outline the increasingly accepted disc:jet connection in the X-ray binaries and how we may be also able to explain this relationship via our internal shocks model.
