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Self-Regulated AGN Heating in Elliptical Galaxies

Daisuke Kawata·Brad K. Gibson
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Abstract

We study the effect of active galactic nuclei (AGN) heating on the chemodynamical evolution of elliptical galaxies and their X-ray and optical properties using high-resolution Lambda-dominated cold dark matter cosmological simulations. Our model considers an AGN as being ``active'' when a convergent gas inflow condition exists within a galaxy's nucleus; otherwise, the AGN is assumed to remain dormant. This induces a self-regulated activity for the AGN, the result of which leads to a stable hot corona and the suppression of significant late-time star formation - characteristics not encountered in traditional chemodynamical models of ellipticals. These properties of our AGN heating model leads to a system consistent with both the X-ray and optical properties of comparable elliptical galaxies.

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Daisuke Kawata, Brad K. Gibson. 2005-01-13. Self-Regulated AGN Heating in Elliptical Galaxies. https://doi.org/10.1111/j.1745-3933.2005.00018.x

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