Contributed Talk - Splinter Magnetic

Thursday, 24 September 2020, 12:02   (virtual room H)

Magnetic fields in the intergalactic medium

Mohamad Shalaby, Avery E. Broderick, Paul Tiede, Philip Chang, Christoph Pfrommer, Ewald Puchwein an
Leibniz Institute for Astrophysics, Potsdam

The origin of micro-Gauss magnetic fields in galaxies and galaxy clusters is unknown. One prominent scenario to create these fields is the amplification of initial seed fields (of unknown nature) through dynamo processes. Thus, the intergalactic medium (IGM) offers a great opportunity to prop the nature of these initial seed fields. In this talk, I will describe recent efforts to use the gamma-ray sky (at GeV energies) to find constrains on the intergalactic magnetic field (IGMF) values and correlation length. The contradictory constraints found offer a strong hint to the existence of cosmological beam-plasma instabilities in the IGM. A highlight to recent efforts to directly simulate such instabilities will also be given.