Orateur
Description
Galaxy cluster-based cosmology is at a crossroads, with the current and next-generation surveys delivering deep sky surveys and large cluster catalogs. In this framework, the use of simulations to calibrate systematics in cosmological analyses is crucial. As a large proportion of cosmological simulations are gravity-only (effectively only evolving dark matter particles), the exploitation of these simulations for cosmology require the inference of baryon properties from the dark matter distribution.
In this talk, I will present ongoing efforts to develop a baryon pasting algorithm and calibrate it on hydrodynamical simulations. We use the BorgCube universe, a large cosmological volume with initial conditions evolved both as a gravity-only simulation and as a hydrodynamic one, using the new CRK-HACC solver. This approach allows us to compare individual cluster-sized dark matter halos in gravity-only simulations to their direct counterparts in hydrodynamic simulations. We use this comparison to tailor baryon pasting to produce cluster gas properties recreating those found in the hydrodynamic simulation. We focus in particular on recreating the pressure and density of the intracluster medium gas, enabling the creation of maps of the thermal and kinetic Sunyaev-Zeldovich (SZ) effects. This work will allow us to create realistic millimeter-wave sky maps from gravity-only simulations which, coupled with efforts to create realistic sky maps at other frequencies, will help us understand systematics in multi-wavelength cluster cosmology.
