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arXiv · 2307.09576

Feedback models in galaxy simulations and probing their impact by cosmological hydrodynamic simulations

Kentaro Nagamine
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Abstract

Feedback effects generated by supernovae (SNe) and active galactic nuclei (AGNs) are pivotal in shaping the evolution of galaxies and their present-day structures. However, our understanding of the specific mechanisms operating at galactic scales, as well as their impact on circum-galactic medium (CGM) and intergalactic medium (IGM), remains incomplete. Galaxy formation simulations encounter challenges in resolving sub-parsec scales, necessitating the implementation of subgrid models to capture the physics occurring at smaller scales. In this article, we provide an overview of the ongoing efforts to develop more physically grounded feedback models. We discuss the pursuit of pushing simulation resolution to its limits in galaxy simulations and the rigorous testing of galaxy formation codes through participation in the AGORA code comparison project. Additionally, we delve into techniques for investigating the impact of feedback using cosmological hydrodynamic simulations, specifically through Lya absorption and CGM/IGM tomography. Furthermore, we outline our future research directions within this field and highlight the progress made by comparing our simulation results with observational data.

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Kentaro Nagamine. 2023-07-13. Feedback models in galaxy simulations and probing their impact by cosmological hydrodynamic simulations. https://doi.org/10.1017/s1743921323000133

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