Self-regulated active galactic nuclei heating in elliptical galaxies.

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 Λ-dominated cold dark matter cosmological simulations. Our model considers an AGN as being ‘active’ when a convergent gas inflow condition exists within the nucleus of a galaxy; 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 lead to a system consistent with both the X-ray and optical properties of comparable elliptical galaxies. [ABSTRACT FROM AUTHOR]