Relics as probes of galaxy cluster mergers
  Galaxy clusters grow by mergers with other clusters and galaxy groups. These
mergers create shocks within the intracluster medium (ICM). It is proposed that
within the shocks particles can be accelerated to extreme energies. In the
presence of a magnetic field these particles should then form large regions
emitting synchrotron radiation, creating so-called radio relics. An example of
a cluster with relics is CIZA J2242.8+5301. Here we present hydrodynamical
simulations of idealized binary cluster collisions with the aim of constraining
the merger scenario for this cluster. We conclude that by using the location,
size and width of double radio relics we can set constraints on the mass
ratios, impact parameters, timescales, and viewing geometries of binary cluster
merger events.
