Oral Presentation

Baryon Pasting: A Novel Framework for Interpreting Next-Generation SZ and X-ray Observations of Galaxy Clusters and Groups

Author(s): Erwin Lau

Presenter: Erwin Lau (Nara Women's University)

We present the latest development of "Baryon Pasting", a novel framework that adopts a physics-based approach for forward-modeling SZ and X-ray observations of galaxy clusters and groups. It enables efficient exploration of the vast astrophysical and cosmological parameter space required for current and upcoming millimeter-wave surveys, while maintaining the physicality of modern hydrodynamical simulations. This makes it a powerful tool for disentangling the impact of cluster and group astrophysics from cosmology. Using the half-sky Baryon Pasted Uchuu lightcone simulation, we demonstrate map-level systematic effects that were previously difficult to quantify. Application of the Baryon Pasting model to the eRASS1 X-ray power spectrum has also yielded cosmological and astrophysical constraints. Looking forward, we discuss how integrating Baryon Pasting with state-of-the-art cosmological simulations and cutting-edge machine learning techniques will fully unlock the potential of next-generation multiwavelength Stage IV surveys through efficient and interpretable modeling of the observable universe.