Merging Galaxy Clusters as Multifaceted Astrophysical Laboratories

The number of known merging galaxy clusters has been increasing at a faster than exponential rate and there are now over 50 known major mergers. I will discuss this boom of discovery and the science that such an ensemble enables. In particular I will focus on the Merging Cluster Collaboration survey of 25 radio relic mergers. I will discuss why this is the ideal sample for pushing the dark matter self-interaction cross-section constraint from its current limit of ~1 cm^2/g to below ~0.1 cm^2/g. This is particularly interesting since cross-sections in the range of 0.3-0.5 cm^2/g have been invoked to resolves the "cusp-core problems and the Milky Way satellite "too big to fail problem".  I will also discuss how we are using this sample in conjunction with laboratory astrophysics experiments at LLNL's National Ignition Facility to solve outstanding mysteries related to plasma shock particle acceleration. Finally I will present preliminary from our investigations into how major cluster mergers are influencing the evolution of their constituent galaxies. It is possible to answer such seemingly far afield questions in a single survey because they have the same data requirements and build on a single core merging cluster dynamics analysis methodology.

Speaker: Will Dawson, Lawrence Livermore National Labs