Relativistic Jet Feedback in Evolving Galaxies

TL;DR

This paper presents high-resolution simulations of relativistic jets interacting with the interstellar medium, showing how they can suppress star formation in galaxies by dispersing dense gas, thus contributing to galaxy evolution models.

Contribution

The study provides detailed parsec-scale simulations of jet-ISM interactions, revealing the impact of jet power and medium properties on star formation regulation.

Findings

Jets with 10^43-10^46 erg/s can inhibit star formation.

Energy transfer from jets disperses dense gas in galaxy cores.

Jet effectiveness depends on jet power, ISM pressure, and gas porosity.

Abstract

Over cosmic time, galaxies grow through the hierarchical merging of smaller galaxies. However, the bright region of the galaxy luminosity function is incompatible with the simplest version of hierarchical merging, and it is believed that feedback from the central black hole in the host galaxies reduces the number of bright galaxies and regulates the co-evolution of black hole and host galaxy. Numerous simulations of galaxy evolution have attempted to include the physical effects of such feedback with a resolution usually exceeding a kiloparsec. However, interactions between jets and the interstellar medium involve processes occurring on less than kiloparsec scales. In order to further the understanding of processes occurring on such scales, we present a suite of simulations of relativistic jets interacting with a fractal two-phase interstellar medium with a resolution of two parsecs and a largest scale of one kiloparsec. The transfer of energy and momentum to the interstellar medium is considerable, and we find that jets with powers in the range of 10^43-10^46 erg s^-1 can inhibit star formation through the dispersal of dense gas in the galaxy core. We determine the effectiveness of this process as a function of the ratio of the jet power to the Eddington luminosity of the black hole, the pressure of the interstellar medium and the porosity of the dense gas.