Galaxy clusters are the largest gravitationally bound structures in the current universe. Originally identified as concentrations of galaxies in the optical, observations in the X-ray and millimeter wavelengths have revealed the bulk of baryonic material of clusters is comprised of a hot, magnetized plasma known as the intracluster medium (ICM, Forman et al. 1972, Sunyaev & Zel’dovich 1972). The kinetic energy of the galaxies and the temperature of the hot gas indicate that in order for the cluster to be gravitationally bound the majority of the mass must be in the form of cold dark matter (CDM, first noted by Zwicky 1937).

Mergers between galaxy clusters represent the latest stage of cosmological structure formation. The most energetic events in the universe, mergers drive shocks and turbulence into the ICM, heating and stirring the cluster gas. These mergers also accelerate relativistic particles, which then produce radio relics and halos (Feretti 2005, Brunetti & Lazarian 2007, van Weeren et al. 2010, Brüggen et al. 2012). Cluster mergers have also revealed the different dynamical properties of the CDM, galaxies, and ICM, seen most vividly in the case of the Bullet Cluster (Clowe et al. 2004, Markevitch et al. 2004). Understanding cluster mergers is therefore vital to answering questions about the detailed physics of galaxy clusters as well as providing insights into the formation of cosmic structure.

The astrophysical literature is replete with simulations of galaxy cluster mergers, from binary merger simulations (e.g., Ricker & Sarazin 2001, Poole et al. 2006, ZuHone 2011, Donnert et al. 2013) to studies of mergers in cosmological simulations (e.g., Vazza et al. 2009, Skillman et al. 2013, Yu et al. 2016). These simulations have often attempted to make predictions for what may be observed in a number of wavebands and made direct comparisons to observed merging systems. However, comparing the results of simulations of cluster mergers to these systems is often not straighforward; at what stage are we viewing the merger, and along what line of sight? To make matters more complicated, different combinations of merger epoch and line of sight can produce qualitatively similar projections of cluster emission, making it more difficult to determine these parameters.

The idea behind this catalog is to provide a way to connect simulations of galaxy cluster mergers with multiwavelength observations of real merging clusters. Producing simulation data in terms of observed quantities at many different epochs and from many different lines of sight provides an opportunity for observers to compare clusters in their observations with a particular merging scenario. The data here may also be analyzed in its own right, to make predictions for what various investigations of real clusters may reveal.