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arXiv · 2412.06495

Feedback from intermediate mass black holes on dwarf galaxy morphology at z=2

Da Bi·Dominik R. G. Schleicher·Andres Escala
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Abstract

This study investigates the influence of intermediate-mass black holes (IMBHs) on galactic morphology, focusing on their evolution within dwarf galaxies at high redshift (z~2). Using high-resolution zoom-in cosmological simulations, we explore how IMBH properties, including seed masses, formation times, and feedback mechanisms, shape the morphology and properties of central dwarf galaxies. The simulations analyze galaxies in both high- and low-spin dark matter halos, under varying conditions of AGN feedback and black hole seeding methods, to assess their effects on gas fractions, star formation, and structural characteristics. Results indicate that AGN feedback, particularly wind strength, significantly impacts galactic properties. Strong feedback results in lower stellar masses, flatter morphologies, and intermediate rotational support, along with prominent central structures and low Sersic indices (n < 2). These findings challenge the applicability of low-redshift diagnostics like Gini-M20 at high redshift. Synthetic JWST observations reveal that pixelation effects may overestimate galaxy sizes, highlighting the complexity of linking IMBH evolution with dwarf galaxy formation and morphology. This study provides new insights into the typical environments of IMBHs in dwarf galaxies and their role in shaping early galactic structures.

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Da Bi, Dominik R. G. Schleicher, Andres Escala. 2024-12-10. Feedback from intermediate mass black holes on dwarf galaxy morphology at z=2. https://doi.org/10.1051/0004-6361%2F202452438

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