Orateur
Michael Kachelriess
(Department of Physics, NTNU)
Description
Combining data from the recently launched Fermi satellite with TeV observations of atmospheric Cherenkov telescopes and low-energy observations has improved our understanding of the sources of high-energy radiation as well as of the conditions in the intergalactic space. After a brief introduction, I show that the non-observation of some TeV blazars in the GeV range by the Fermi satellite lead to the first lower limit on the intergalactic magnetic field (IGMF). Moreover, the IGMF has to fill more than ~50% of the Universe, suggesting its primordial creation in inflation or phase transitions. Finally, I discuss the constraints on these mechanisms.
Author
Michael Kachelriess
(Department of Physics, NTNU)