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arXiv · 2210.12886

X-ray Emission from the Interstellar and Circumgalactic Medium of Elliptical Galaxies based on MACER simulations

Aditi Vijayan·Bocheng Zhu·Miao Li·Feng Yuan·Luis C. Ho
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Abstract

Interstellar (ISM) and circumgalactic mediums (CGM) around galaxies are linked to several physical processes that drive galaxy evolution. For example, the X-ray emission from the CGM gas around ellipticals has been linked to the AGN feedback occurring in the host. Upcoming telescopes, such as HUBS with ~2 eV resolution, can provide us with deep insights about the hot gas properties of such galaxies thus constrain these processes. In this project, we discuss X-ray emission of the ISM and CGM of elliptical galaxies simulated using MACER code. We generate X-ray emission data from the MACER simulations with various feedback models and produce mock observations for an instrument with high spectral resolution, which is a necessary step of selecting sources for the future observations with planned mission such as HUBS. More importantly, we establish connections between the physics of AGN and stellar feedback with the emission spectra from the ISM and CGM to investigate the possibility of using observations to constrain feedback models. We fit the X-ray spectra from these simulations with standard fitting procedures and compare the retrieved physical properties with their counterparts from the simulations to understand whether the future high-resolution observations can reliably reveal the properties of the gas in the galaxies.

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Aditi Vijayan, Bocheng Zhu, Miao Li, Feng Yuan, Luis C. Ho. 2022-10-23. X-ray Emission from the Interstellar and Circumgalactic Medium of Elliptical Galaxies based on MACER simulations. https://doi.org/10.1093/mnras%2Fstad2107

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