By Fred Jennings,

In this work, we investigate the X-ray properties of a sample of galaxy groups and clusters (M₅₀₀ ~ 10¹³-10¹⁵ M_⊙) at low redshifts in Simba, a large-scale cosmological simulation with a unique galaxy evolution model. To do this, we create mock Athena/WFI observations of each halo and analyse them using MOXHA - a software package we have developed to wrap and extend the X-ray mocking software packages PyXSIM and SOXS. Athena/WFI has a wide field of view and a high count-rate capability, meaning we can make very good observations of halos at low redshifts. This is critical for obtaining observations quickly with few pointings and gathering enough photons to be able to de-project and perform spectral fits on the X-ray signal. Using these mock Athena observations of a realistic, evolved population of simulated halos, we can accurately measure the hydrostatic mass of real galaxy groups and clusters and their scaling relations. These measurements are crucial for cosmological surveys and also for understanding the nature of the feedback from the central supermassive black hole at the centres of clusters and its effect on the surrounding hot intra-cluster plasma.

Access to the manuscript in ADS.